You’re a day away from a release deadline, and disaster strikes; two of your four QAs, half the team, are struck down with a nasty stomach bug. We need to sort out immediately what that means for our release; what testing work has already started and now needs to be reassigned, and what hasn’t even been started yet, and will therefore probably get dropped out of this release entirely. Does our Agile Board help with such decisions by making it instantly obvious what has started, and what hasn’t?

This is the kind of common real-world situation that can be helped by the good use of “buffer states” on your board, and that is the topic of this article.

As we know from previous articles, an Agile Board shows the workflow of a team, the series of steps its work goes through on the journey from conception to finished. Along the way the work is passed along a virtual production line, with various different combinations of people engaging in different value-adding activities, until we get the finished product.

The ideal is that the delays between (and within) each of these value-adding activities is minimal or even nil, the appropriate metaphor being a slick sprint relay race:

Unfortunately the real world is rarely anything like this. A good team might approach this ideal in dealing with an Emergency, where everything is sacrificed for speed whatever the cost in disruption elsewhere, but for normal work there will most certainly be gaps where work sits idle. In fact, when measured, most work spends a shockingly high percentage of its life sitting around unattended, waiting to be picked up. The metrics of work idleness*, ‘touch time’ and ‘flow efficiency’, will be the topic of a future article, but for now it should be clear that reducing such idleness to a minimum is one of the main objectives of a good team, and visual management of idle work is essential to that goal.

This means separating out such idle states and making them visible as columns on an Agile Board, appearing as ‘in-between’ columns or ‘buffer states’ that separate out the columns for the main value-adding activities.

If you’ve ever worked with an Agile Board you have likely come across buffer states, even if you didn’t think of them that way. Even the simplest board of all, “To Do — Doing — Done” is really nothing more than a couple of buffer states around a single activity, and it can be rewritten to a format that makes this explicit:

Let’s apply this thinking to the example workflow sketched out across two previous articles (here and here), to see what we can learn. After such an exercise we will have a deeper understanding of this workflow, and will have a conceptual framework for further tweaking and improvement. Here it is again, a complete workflow across a dozen columns:

These columns tell us that we started with an idea, and then applied the following list of discrete activities to it:

1. Triaging
2. Ticket Prep
3. Development
4. QA
5. Sign-off
6. Deployment to live

So what happens if we take this list, and just wrap each item in buffer states? Let’s do that for the first two adjacent activities, Triaging and Ticket Prep, and see what results:

The first thing to notice here is that we end up with two buffer states next to each other, which makes no practical sense. A ticket which has completed Triage simply is ready for Ticket Prep, so the two columns Triage Complete and Ready for Ticket Prep are duplicates. One of the redundant columns must be removed; it doesn’t matter much which one goes, but it’s nonsense to have both.

With this in mind, let’s see what happens if we apply just a pre-activity buffer, ‘Ready for X’, before each of the six main activities in the workflow. This gives us the 14 column workflow below, with the buffer states highlighted; collectively, they now show all the states where no value-adding work is being done.

Comparing this to the original workflow, two useful steps have been lost, Handshaking and Code Review. These are neither buffer states, nor a main activity state. Instead, both of these are reviewing steps – Handshaking is a review of the Ticket Prep activity (to see if it was done to the required standard), and Code Review is the same for the Dev step. Let’s insert these two states back into the workflow, renamed to be consistent with the other steps as “Ticket Prep Review” and “Dev Review”. This gives us the 16-state fully-buffered workflow below:

Now let’s compare this to the original 12-state workflow, with its (three) buffer and (two) review states highlighted:

So which of the two is better? The differences come down to column naming (which is a matter of taste), and whether every discrete activity is buffered. Is it actually better to buffer every activity?

Arguably it is. In a previous article on triaging, we saw that that buffer states make it easier to describe the precise meaning of each column, as you are no longer munging both waiting and doing into a single column. Is that sufficient to declare we should always buffer every activity on a board? Not quite; there is a countervailing pressure, that Agile Boards with too many columns can become cumbersome and hard to scan and read, whether they are physical or implemented in software.

Physical boards with 16 columns are relatively rare; you need a mighty wall to display it on, and there aren’t too many of those available in most offices. For software boards, the limitation is the legibility of a screen with many columns on it. If everyone in your office has monitors with huge resolution, or (perhaps soon!) Minority Report style VR screens, you won’t be affected by this limitation. But most of us will sadly run out of wall inches or readable pixels, and so there is some reason to limit the number of columns where possible, unless you wish to split the board in two (which can be done – I will cover this in a future article).

Let’s return to our original 12-state workflow, and see what buffer states are and are not included. It turns out that none of Triaging, Ticket Prep or Sign-off are buffered, and Deploying to Live is effectively unbuffered as well, with one column (‘Ready for Live’) representing both buffer and activity itself. Activities that are buffered are Dev and QA. What are the reasons for treating different activities in this way?

In the real teams where this very Agile Board setup worked well, the unbuffered activities of Triaging, Sign-off and Live Deploy were relatively quick, uncontroversial and unlikely to go wrong, and so were able to function with a less detailed board representation. Coding (Dev) and testing (QA) are almost always, by contrast, multi-factorial and highly complex activities, drawing on the bulk of the team’s manpower and budget, and with equivalently high need for transparency, hence the decision to buffer those columns.

Between Triaging and Ticket Prep a buffer might have been helpful, but both activities were owned by the same Product sub-function, and so tended to be run by the same small group of people. The resulting good interpersonal communications and the ease of ‘handing work over to yourself’ meant that extra detail on this part of the board was unnecessary to smooth team operations.

So it turns out that the buffering decisions on this Agile Board were well fitted to its context; there is a rationale for buffering some activities but not others. A fully buffered Agile Board may be a wonderful thing – but if you can reduce column count without compromising the flow of work, that is also fine. And the only test that matters is the empirical one of whether your setup works well in practice.

Finally, I will show a slightly different kind of board setup which you sometimes see in the literature and in the workplace. Many Agile Board software systems do not allow sub-columns (which is why my examples show simple columns that are the height of the whole board), but some software systems do, and of course on a physical board you can have any setup you like within the available space. Allowing sub-columns leads to slightly different board layouts such as the following, taken from this book:

Whatever you think of the choice of just three main activities, this board design does neatly buffer each activity with a sub-column titled ‘Ready’, and is a common layout that you should be aware of as a variation.

In conclusion, we have drawn attention to important ways that Agile Board columns can be classified into principal activity, buffer and review states. We have seen that where activities are complex and expensive, you may expect a greater benefit from going into more detail on your board by adding buffer and possibly review states. Where activities are relatively quick and straightforward, you may wish to forgo such details and see if a single column for the activity will serve your needs. As ever, it is the context that decides, and it is up to you to find what setup and tweaks work optimally for your teams.

*Note: this is idleness of work, emphatically not the quite different concept of the idleness of people. The former must always be cracked down on, but the latter is a more nuanced thing; indeed, having some slack built in to people’s normal work practices is essential to allow for responsiveness. This will, again, be a topic for a future article. 

In a previous article we introduced the core concepts of triaging: the origins of the term in emergency medicine, what it means to have triaged a ticket in the world of software development, and the basic metrics around doing it well. In this follow-on article, we will look at a few of the subtleties in this very first part of a team’s workflow, the steps from ticket creation through to finishing triage.

So what are the ways these steps can vary between teams? Let’s consider a few:

Who can create tickets?
Teams can and should formulate (then publicise, and enforce) their own rules around this. At one extreme, it could be “anyone at all”, even people outside the organisation. Or you could be more restrictive: only people inside the organisation, only people in this particular department, only members of this team, only selected members of this team, or only one particular person.

There’s a trade-off here: the smaller the number of people who are allowed to create tickets, the easier it is to standardise the ticket creation process around your optimal set of requirements (eg what data fields must be filled in so a ticket is triageable), but the more you need to work to establish good comms methods for allowing outside people’s work requests to be translated into tickets by these Creators. If, on the other hand, Ticket Creation is open to many people, the team needs to carefully police the quality of created tickets, and publicise guidelines around doing so. There’s no right answer here – each team has to figure out their own arrangements by an empirical process of trial and error.

Who can triage?
Again, this is contextual, but a typical arrangement is that the Triage Team is a combination of internal team management roles, people with such titles as ‘Tech Lead’, ‘QA Lead’ and ‘Product Owner’.

What needs to be recorded?
Agile doesn’t mean chaos or never writing anything down, but there’s no point being wasteful and requiring unnecessary documentation either. With triaging it is often sufficient to take less than a minute to make just a single comment (eg in a Jira ticket) along the lines of “Ticket triaged by Rob and Jenny – bottom of the backlog”. That simple audit trail can save a mountain of pain later.

How do you keep on top of your triaging?
Given that we want Triage Time and Untriaged Count to be as near to zero as possible at all times, we need untriaged tickets to show prominently somewhere, as a reminder that there is triaging to do. Jira, arguably the most powerful work management system commonly used by software teams, tends to dump minimally-filled-out new tickets right at the bottom of the backlog, where they might not get looked at for a very long time. If you are in that situation, you need to have a robust team process to combat Jira’s tendency to hide these new tickets away.

When I run tech teams, I often take on myself the task of scanning the bottom of the Jira backlog several times a day for recently-created, untriaged tickets. I would then move such tickets into the ‘Triaging’ state, stick them (temporarily) high up the backlog so they get noticed by all on the team’s Agile Board, I comment/assign them so my Triage Team are additionally notified by email to make the priority call, and as appropriate use other comms methods (F2F, IM etc) to make sure they know of the incoming wounded. None of this is very onerous if done “little and often”, and it has worked very well in multiple teams.

What options are there for representing triaging on an Agile Board?
In an earlier article we looked at one simple pattern for representing the early part of a team’s workflow, where triaging itself is represented by a single step, with no buffer states on either side:

The meaning of the columns in this case would be:

Idea: a ticket has been created in the system, nothing more. It may or may not be fit for the next step in its life. If not, this could be because it contains mostly garbage, or perhaps because it hardly contains anything at all. The creator, with or without help, must rectify this before the ticket can progress.
Triaging: in the absence of any buffer states, this column contains tickets that have been assessed as ‘fit to be triaged’ but where that process has not yet started, and those currently undergoing triaging.
Ticket Prep: in the absence of any buffer states, this column now represents tickets that ‘have been triaged and no more’, and tickets where in addition ‘more detailed ticket prep has already started’.

An alternative Agile Board setup, with buffer states either side of the main Triaging activity, might look like this:

This time the column semantics are as follows:

Idea: a ticket has been created in the system, nothing more. Nobody other than its creator necessarily knows what’s in it.
Ready for Triage: this “pre-state buffer” means that someone has checked the information in the ticket, and verified that it is sufficient for a triage decision. If such a check reveals that a ticket has failed to meet this standard, that ticket stays in the Idea state and is appropriately reassigned and commented.
Triaging: the triage itself is happening now.
Triage Complete: a “post-state buffer”. Triaging has finished, meaning that the ticket has been placed in an appropriate slot in the team’s priority-ordered list of work. Nothing more has yet happened.
Ticket Prep: the next major step in the ticket’s life after triaging has now begun

This extra detail on the board has a cost and a benefit. Having a large number of columns can cause issues both with physical boards (are they wide enough to fit all the columns?) and software boards (does your monitor have enough pixels to display all columns legibly?). The benefit is that you are more accurately able to represent what is really going on – see how much easier the column semantics were to explain in the second example above. Teams must figure out by trial and error what columns work best for them, but I often find that you can pare columns down around the activity of Triaging, but definitely need buffers around some downstream activities such as Dev and QA. Buffer states will be discussed in more depth in a future article.

How exactly do I collect Triage metrics?
The two metrics introduced in the previous article, Triage Time (average time to get new tickets triaged) and Untriaged Count (how many current tickets haven’t finished triage yet), are read off your Agile Board, and so of course depend on how the board is set up. In the two examples we are discussing, the detailed setup contains three columns where tickets would count as untriaged, and the simple setup just two, as illustrated below. The diagram below shows how the columns map to each other across the two variants, and the “Triage Line” indicates the point at which triaging has been completed in each case:

To conclude, if you care about smooth and efficient software delivery, there’s much important work to be done well before the first line of code is written. It’s notable that many teams focus only on modelling and tweaking the delivery part of their workflow, and sorely neglect the upstream steps, such a triaging. This neglect only stores up problems that come to light during delivery itself, when they are much more costly to fix.  Hopefully between this article and the previous one you have the guidance you need to put a robust Triage Process in place in your teams; the rewards for doing so will be felt throughout the rest of your work.

Triaging is a critical step in the lifecycle of any piece of work. I touched upon it in a previous article, and here we go into it in more depth.

The term has a medical origin. Deriving from the French triager, meaning ‘to separate out’, it is best to imagine either a military hospital near the front (known to many as a MASH unit), or the Emergency Department of a civilian hospital. New wounded are brought to the unit at unpredictable times, in unpredictable quantities.

The initial processing of these new arrivals is urgent, and must be done quickly and efficiently; there are, after all, limited resources of medical care to go round, so what is available must be used as efficiently as possible, where you will get the most reward (lives saved) for the effort. To achieve this goal this the wounded are ‘triaged’, which means divided into three categories:

• the worst cases – they will die anyway. These ones should be made as comfortable as possible, but they are actually not the highest priority, as medical intervention will make no difference.
• the minor cases – they will survive anyway. Obviously these are not the highest priority.
• the ones where immediate action will make the difference between life and death. It is these that are the highest priority – they must be prepped for surgery (or whatever is appropriate) as fast as is humanly possible. Every second counts.

Thus medical triaging amounts to a quick prioritisation exercise. It is done on the basis of limited information (you can’t spend hours investigating each new wounded case, you have perhaps minutes or seconds), but you obviously can’t do it on the basis of no information. The skilled triager knows exactly how much information is needed to make the triage call; he gathers that amount (no more, no less), makes the decision, then the patient is moved on to the next stage of their care, and the triage team moves on to the next wounded person, until all have been triaged.

Note that the triage team does not administer treatment – that is the next step. In some cases, that next step might follow one second later, but it is still conceptually a next step, possibly performed by a different person in a different place. The triager has to keep going with the rest of the triage as their highest priority, because the next case could be even worse – until you’ve looked, you just don’t know.

Triage is therefore complete when every single new case has been sorted into the correct category, in other words when the untriaged count = 0. Note that even if the helicopter brings in just one single wounded soldier, you still can’t afford any delays in starting triage, since you have no idea what state that person is in. That single guy could be your top general, right on the boundary between life and death, and a lackadaisical triage process means the chance to save him could be lost.

All of this has parallels in the world of software development, except – hopefully – there’s less blood. Instead of wounded soldiers being helicoptered in to base, the raw material for triaging is new tickets. Starting as soon as possible after new tickets are created, the triaging itself means sorting them into their correct position in the priority-ordered list that is the product backlog. That ticket is then triaged and the triage team moves on to the next one, until untriaged count = 0, when triaging is complete (for now), and the next steps can begin.

The one disanalogy between medicine and tech triage is that a new ticket might not have enough information to be triageable – some people write absolute gobbledigook in new tickets, or barely write anything at all. In that case you send it back to source for more information, and try to triage it again when it returns. There’s no medical equivalent of that – you wouldn’t send a soldier back to the Front to get their wound explained more clearly.

What is the tech equivalent of the three medical triage categories above? One way to think about it is that you are choosing between 6 broad slots in the backlog for a new ticket. For each new ticket, you need to decide whether the right place for it is…

1. …right at the very top of the backlog, ie it is the most important thing of all. It is quite likely to be an emergency to have dropped in this position, so your team needs a way to deal with emergencies.
2. …a specific slot in the top quarter of the backlog. If so, pick the precise slot in this quarter with some care, as much of the work this high up will have been started already, and is progressing across your Agile Board. This new ticket might need some extra attention to get it to Ready for Dev quickly, and once there you might then put it right at the top of the R4D column, meaning it’s the very next thing the devs pick up whenever one becomes free.
3. …somewhere in the second quarter of your backlog. If so, don’t bother being so precise about exactly where in this section it drops – it’s likely to be a bit of time before this work starts advancing across your board, and the backlog will probably have been revised several times before that happens.
4. …somewhere in the third quarter of your backlog. Even less precision is merited here. Some of this stuff will never get built at all, frankly.
5. …somewhere in the last quarter of your backlog. Most of this stuff will never get built, and you should consider carefully whether this ticket is even worth preserving at all. If not, you are at the next option…
6. …the rubbish bin, ie the ticket is worthy only of being thrown away. Maybe it’s a dumb idea, maybe it’s not such a bad idea but there’s just no chance of this happening on any timescale that people remotely care about. Depending on what ticket management system you are using, you may actually delete it, or perhaps just resolve as invalid, or won’t fix, or similar.

These 6 choices are shown in the pictorial example below. In this case, a new ticket ends up being slotted into the bottom quarter of the backlog, option 5:

Once triage is complete (well done! untriaged count = 0), your next duty is to make sure all interested parties know of this triage decision, including whoever requested/created it. In some systems (eg Jira) it may be sufficient to add them as Watchers to the ticket so that they automatically receive email notifications of updates; in other contexts, other comms may be necessary. When these parties do find out how you’ve prioritised their work, they may be fine with it, or may vigorously disagree, but it’s best to have those discussions out in the open immediately, rather than to leave potential future conflicts stewing away in the background.

It’s in everyone’s interest – the team, suppliers, customers, stakeholders – to have a good triage process – there may be some horror lying in wait in that unopened ticket! The metrics around this process are a) ‘Triage Time’, the time it takes for newly created tickets to be triaged, and b) ‘Untriaged Count’, the number of tickets in the system that have not been triaged yet, and are therefore of unknown priority. The aim is to get both metrics as low as possible. Oddly, I have never seen the Triage process specifically called out as a key measure of how well a team is running, and yet in my experience there is a very strong relationship between being a good team, and doing the basics well – and triaging is one of the basics for sure.

In the next article we’ll examine the steps from ticket creation to triage completion in more detail. For now we can summarise the best practice lessons for triaging as: do it quickly and efficiently, don’t let untriaged tickets lie around, aim to get your untriaged count back to zero daily if possible, and let the concerned parties know the results of your triage as soon as you have done it. If you do all this, you’ll be one of the relatively rare teams that have a tight Triage Process, and you’ll have taken a big step towards becoming a good team.

So a ticket has failed QA, and the fail’s a bad one, it needs to be fixed for sure. A dev (probably the one who coded it in the first place) needs to change the code, and then it needs re-reviewing, re-testing, and hopefully will pass second time round.

This is one of the most common situations in a software development team (unless you’re the one team in the world who manages, without cheating, to produce no bugs at all). How should these steps in the life of this ticket be represented on an Agile Board?

There are two basic patterns that can be used. We’ll start with the most commonly used pattern, the ‘Looping Method’, which can be summarised as ‘move the ticket left, back to the In Dev column, for the code amends, and then to the right through Code Review, Ready for QA etc, just as it did on the first iteration. In fact, every time a developer needs to work on that ticket, it jumps left to In Dev for the new code changes, then moves across again to the right’.

Note that there’s nothing special about the In QA column we are using in this example. The Looping Method applies equally if the bug had been found in different column, such as Sign-off, or Ready for Live, it’s just that the ticket would just have to jump that much further to the left to land back in ‘In Dev’, so the loop is bigger.

A pictorial representation is below. The ticket reaches In Dev for the first time and is assigned to a developer to write the initial code. It moves rightwards through Code Review and Ready for QA, then a tester picks it up at ‘In QA’, assigns it to themselves and starts testing. The nasty bug is found, and the ticket jumps three columns to the left and is reassigned to a Dev. This ticket will now loop between columns until every nasty bug is fixed, and it can finally move on beyond QA. At that point more bugs might be found, and more looping will start.

It’s easy to see why teams might work in this way –  it’s just doing the same thing on the second, third or fourth iteration of coding as happened the first time. Is there any problem here?

In fact there is. Due to this looping, tickets are jumping horizontally whenever a different sub-team (often, but not always, Dev) needs to work on them next. As a result you are now unable to use the triangulation method of reading a board, as this method uses both horizontal (‘Done-ness’) as well as vertical (‘Priority’) planes to work out the correct order of tickets. But there is no alternative to triangulation to reliably order all tickets on a board, so the Looping Method destroys a key property of a good Agile Board, that it broadcasts to everyone what to pick up next.

In fact the triangulation method tells us that moving tickets left is functionally equivalent to de-prioritising them, as moving left means a ticket is ‘less Done’, and therefore less urgent. But a moment’s thought tells us that it is simply not true that finding a bug deprioritises a ticket, so on the Looping Method our board is Not Telling The Truth – a big problem.

Let’s consider which of the following options we would prefer an available Dev to pick, other things being equal: a) fix a bug on a ticket they had previously coded, b) work on other code that hasn’t reached QA a first time, or c) start something entirely new? The answer is clearly a), to fix the just-found bug. There’s a good chance of getting such a ticket finished and off the board with relatively little extra effort – it genuinely is closer to Done. Remember, it is only finishing tickets that provides any value to the organisation, so it would be crazy to deprioritise a ticket just because it needs some dev attention.

In fact the behaviour we generally want to encourage on finding a bug is for developers and testers to work in close collaboration, with tight feedback cycles of testing, recoding, reviewing and retesting, until the bug is fixed. If each step suffers delays, even relatively minor bugs can take an absolute age to fix, with both parties context switching each time, and quite possibly the underlying codebase changing considerably as other tickets flow to the right. Deprioritising tickets will lead to loss of focus and increase in delays, so that’s the very last thing you want to do to a ticket when it fails QA.

Indeed, if you allow or encourage Devs to start on new code in preference to fixing already-written code that just failed QA, the team will quickly end up with a mountain of unfinished, buggy work piled up in the middle of their board. Such a team – great at starting things, but lousy at finishing them – can only be very unproductive.

Of course, not all teams using the Looping Method sink that far. Good practices outside the Agile Board – strong leadership, effective meetings and internal comms – might compensate for a deficiency in how the board works. But good board usage is designed to make all this far, far easier. What is the alternative practice we can use here?

The alternative is the ‘Tickets Don’t Move Left’ method (TDML)*. It says simply that when a ticket requires the help of some other part of the team to move onwards, you leave it where it has reached on the board and reassign. This way the board continues to represent Done-ness accurately, so the triangulation method works and you can always use your board to figure out the Most Important Thing To Do.

Let’s see this method in diagrammatic form.  The first two parts are exactly as before, but when the ticket reaches QA and the bug is found, it stays in the In QA column and is reassigned to the Dev for re-coding:

And then when it’s time for a second round of Code Review on the recoding, the ticket again stays where it is, but is reassigned to a different Dev for that review. And then it will go back to the QA for retesting, again, without moving column:

This is really a trivial change in board usage. Team members just have to get used to relying on the Assignee field to know what to pick up, and understand that they might need to pick up from any column on the board, rather than only ever bothering to check one particular part of the board (for Devs this would typically be the In Dev and Code Review columns).

I have moved teams from the Looping Method to TDML method in a single day. It really isn’t that hard, and the payoff is enormous; we stop working in a way that continually destroys a board’s ability to clearly represent the priority of work. The triangulation method works, so you get the huge benefit of easily reading your board and knowing what to pick up next.

On top of this, there is a more subtle attitudinal change when you become accustomed to looking across the whole board to find your work. A large part of the Agile mindset is to have everyone working and thinking as a team, rather than the siloed mentality of a Waterfall process, where in strict order Analysts do X, then Devs do Y, then QAs do Z, and the success of the thing-as-a-whole is always someone else’s problem.

The correct team attitude is that the entire workflow is a shared responsibility. In a truly Agile team it’s not your narrow job title that defines what you do; your job is to use all your skills to help the team get its highest priority work all the way to ‘Done’. And TDML is the perfect visual representation of that approach, where everyone is co-operating fluidly with everyone else, as need dictates, to maximise the value of the whole, with a collective sense of ownership of the flow of work.

In that sense the board usage recommendation of this article is very powerful. Though TDML is on one level no more than a minor tweak to how teams use an Agile Board under some circumstances, it has a strong resonance with how team members need to think and act such that they are genuinely a team, working together constructively towards a common goal.

*a caveat to the TDML rule: as with all rules, there is a superior rule which takes precedence: ‘Common Sense Always Wins’. So if a ticket is ever simply in the wrong place on a board, you should always correct it and Make The Board Tell The Truth, whether that involves the ticket moving North, South, East or West. Even the best rule can be taken too dogmatically; it doesn’t make it a bad rule, it just means you need to use Common Sense at all times.

Note: I am indebted to David Shrimpton for introducing me many years ago to the key concepts in this article.

EDIT: this article from June 2021 makes many very similar points:

Don’t move items backwards on the kanban board: “Let’s imagine a car production line. If a defect was detected at the stage of installing the door but it was related to the earlier phase, the car is not moved back to the source of error, but rather kept in the place where the defect was detected. Instead, people swarm around it and try to fix the problem.”