Too much work. Too little time. It’s a constant for many businesses struggling to keep pace with client demand, company growth, or industry disruption. One strategy that leaders can implement to alleviate pressure and free resources is limiting work-in-progress.
Work-in-progress limits (WIP limits) constrain the number of projects being worked on at any given time, allowing teams to deliver higher-quality work in shorter timeframes. It sounds simple enough, but it’s more nuanced than capping the number of items on your to-do list – especially for those operating in knowledge work.
In this article, we’ll explore WIP limits, explain their benefits, and share practical tips you can follow to benefit from this strategy.
What is limiting work-in-progress?
Limiting work-in-progress involves cutting down the volume of active work. The goal is to reduce the number of work items being worked on (in progress) at any one time, so teams (or individuals) can focus their energy on actually finishing what’s most important or digging into what is stopping them finish the work. How this plays out in practice depends on the nature of the business. For example, it might mean working on one new feature at a time or capping the number of projects in development.
Organizations that implement the limiting WIP mantra can reap significant benefits, one being reduced lead time. Lead time is the time it takes from entering your workflow, to its completion. The more work entering the system, the thinner your teams are spread, and the longer it takes for your team to produce a finished product – it’s a mathematical fact defined succinctly by Little’s Law.
Little’s Law is a theorem that reveals the average number of items within a queuing system using the average waiting time of an item and the average number of items entering the system per a given unit of time. Think supermarkets. How many people in a checkout queue depends on the number of new customers joining the queue and the length of time the cashier takes to checkout a customer. The formula looks like this:
W = L / λ
- W represents the average waiting time of an item.
- L represents the average number of items within a queuing system.
- λ represents the average number of items entering the system per a given unit of time.
Little’s Law can be adjusted to calculate the capacity of systems:
- W becomes lead time (or the time an item spends within a system)
- L becomes WIP
- λ becomes throughput or production output
Altogether, the formula is:
Lead time = WIP / throughput
So, the fewer WIP items you have, the shorter your lead time.
In addition to faster lead times, the benefits of WIP limits include:
- Deliver Value Faster: As the complexity of the work and problems we solve is ever increasing, adding WIP limits helps the amount of active work progress faster. The focus shifts from starting new work to completion of inflight work, as a result the conversations change to what can we do to complete “In Progress” work items from let’s start as many as we can. Starting and not finishing is an illusion of progress. progress is measured by what is finished.
- Visible prioritization. With fewer tasks on the table, teams quickly learn that they need visibility into priorities to make trade-off decisions and focus on the highest priority activities. Leaders with shared, visible priorities can therefore be confident their teams and resources are delivering maximum value. Without limiting WIP, priorities can often be assumed, and teams can give the impression they are working on something when they are still stuck on another task.
- WIP encourages continuous process improvement. Limiting WIP introduces slack time, this is the time not actively and directly working on customer requests. Slack time creates opportunity through time and space for system improvements, improving processes and practices that will act as enablers to deliver more. Examples include test automation and professional development.
- Easier identification of bottlenecks. By limiting WIP, teams and leaders are more in tune with work on the go. This allows for easier identification of bottlenecks, which team members can then address. Without a focus on limiting WIP, the causes of the bottlenecks become embedded in the system. They are 'how things get done around here' and become a permanent brake on speed of delivery.
- Less context switching. Context switching occurs when workers switch between tasks or tools, and in knowledge work, it requires a significant amount of mental energy. According to a report out of Cornell University’s Ellis Idea Lab, people take an average of nine and a half minutes to get back into a productive workflow after transitioning between apps. In addition, 43 percent of people believe switching tasks leads to fatigue. Another study found just 2.5 percent of people can effectively multitask – for the rest of us, doing more than one thing at a time erodes productivity. Think of it like reading two books at once. Moving between the two will sabotage your enjoyment of both and greatly increase how long it takes to finish either book.
- More concentrated resources. Concentrating an organization’s, team’s, or individual’s effort ensures a higher-quality output. A University of Exeter review found that people are more prone to error immediately after switching tasks. There’s also the wasted effort factor. When resources are stretched, teams might end up returning to or starting tasks discussed weeks or months ago. At this point, information recall is poor, forcing the team to redo or reopen work or decisions that were partially completed weeks or months before.
From manufacturing to knowledge work
The concept of WIP limits originated in manufacturing. Generally, manufacturers monitor their WIP materials levels across three stages of production:
- Raw materials, which have not yet been worked on
- Work-in-progress materials, which have had some work applied but are not yet completed
- Finished products, which are ready to be shipped and sold
WIP materials are physical, tactile, and visible. You can walk by a workstation and, quite literally, see the pile of semi-finished products. The quantity of WIP materials is very obvious and very much in your face, and so, too, is the need to implement WIP limits.
However, when we move into the context of knowledge work, WIP is a whole other beast. You could visit an employee at their desk and stare over their shoulder at their laptop screen for a full day without comprehending the impact of WIP. You could schedule a Zoom meeting with one of your teams, and unless they specifically tell you that they’re drowning in unfinished tasks, you could leave the meeting thinking everything is under control.
Bottlenecks are also ephemeral. In knowledge work, the nature of tasks changes rapidly, and the rate at which tasks enter the system is seldom constant. Everything is variable, and bottlenecks rarely stay in the same place for long.
How can leaders limit WIP in knowledge work contexts?
The question begs: How can leaders reap the benefits of WIP limits in the context of knowledge work? There is no quick fix. Instead, you must commit to a continuous process of tweaking, assessing, reflecting, and refining.
To get you started, here are eight steps you can take to effectively limit WIP, concentrate your resources, and drive higher-quality outputs.
1. Accept that you are a part of the problem
The first stage is recognizing your contribution to the number of tasks on your team’s plate. Consider the impact too much WIP has on your business more broadly. All the busy work, the half-finished projects, and half-baked products are taking away cycles. They prevent you from reaching your goals and achieving what matters most to your vision.
Invest time in learning the basic principles of lean, so you can actually walk the walk and become not just an advocate, but a role model (more on this below). For example, if you add a priority item to a team's backlog, make it a practice to remove a priority item (or two) at the same time. If your team needs to start doing a new thing, what existing thing can they stop doing?
2. Translate theory into practice
There’s a big difference between believing in the value of WIP limits in theory and leveraging the real-world benefits in the specific context of your organization. You might believe that exercising five days a week or reading before bed can change your life for the better, but it’s only when you commit to action that you realize the benefits.
So, start by identifying where bottlenecks often occur in your teams’ workflows. Then, brainstorm practical ways to reduce or eradicate these bottlenecks to ensure work-in-progress is finished before new work is started.
You might also like to consider personal WIP limits. Some teams and individuals may benefit from (rarely) higher or (more commonly) lower caps.
Taking real, meaningful action could be as straightforward as tackling emails and calendars, for example.
Open your inbox. If you are like most people, it’s packed with unread and flagged emails you need to read, process, and deal with. These emails hang around for days, weeks, and even months. They are silent to-do lists. The good news is you have control over your inbox and can set parameters to limit the amount of noise you need to sort through.
For example, only open an email to process it. Never close it without dealing with it then and there, whether that means doing, deleting, deferring, or delegating (dubbed the 4 Ds of effective time management).
A best practice might be dedicating your time to either email or meetings – never both.
Next, open your calendar. Almost every person you bump into in a knowledge environment – leaders and employees alike – has eight hours of meetings scheduled. How many of those are necessary? How many do you really need to attend? If the answer is “all of them,” that’s a sure sign you have too many projects running simultaneously. And if the answer is “half of them,” get yourself out of the unnecessary half.
There are two ways you can minimize the number of meetings in your calendar:
- Block out time to work on existing projects. That way, you have guaranteed time to dedicate to tasks you’ve already started throughout the week.
- Set a parameter that rejects calendar invites or meeting requests when a certain milestone is met. For example, you might block calendar invites after you have 4 hours of meetings scheduled in one work day. This keeps your weekly meeting hours to a manageable level.
3. Have open conversations about priority
WIP limits force a conversation around priority. When every project and every task is moving forward – albeit slowly – priorities are less relevant. As long as whoever is asking can see some movement on their request, however microscopic, they’ll likely be satisfied. However, if only a small number of requests are being worked on, leaving the others queued with no attention or activity, those same stakeholders may not be satisfied. Leaders must have open and honest discussions with these stakeholders, so they understand and agree with the priorities you have established.
4. Encourage intentional communication
Intentional communication is critical to achieving and sustaining WIP limits, but it takes explicit rules and follow-through to keep emails and chat messages under control. Here are some areas to consider:
- How is email used? Is email used for every question about every project? Or is it reserved for external and more formal communications? You can’t control the emails coming through from clients, vendors, and other external sources, but you can control how you and your people use email.
- How are CCing and BCC'ing used? Do leaders need to be copied into every communication? If so, why? You want to reduce the number of emails landing in your inbox, and that means being selective about the communications you ask to receive.
- Are you including more than one message per email? The more complex the message, the more time and effort it takes to reply.
- How are instant messaging platforms like Slack or Teams used? Asynchronous chat functionalities can be an effective complementary channel to email, especially for internal communications. Instant messages can be organized and labelled, are shorter, and require less time and mental effort to compose and respond to.
- Are you and other team members engaged in communications you don’t need to be in? Your time is limited, so remove yourself from email chains and chat channels that you don’t need to contribute to or can’t add value to.
- Are you adhering to your communication rules? Leaders are role models, so it’s crucial change starts with you. Set expectations with both words and actions, and be consistent and clear with your messaging.
5. Recognize that some tasks are more time-intensive than others
The size of work picked up by your team is critical to the success of your WIP limits. Say your team has a WIP limit of three. One day, a very large project comes in, one that will demand several months of work. Your team takes it on, but now they’re fully booked. In short, that one project represents more than a third of their capacity, so they can't take on additional projects, or at least are limited to no more than two other projects. This large project effectively reduces active capacity by a third (at least).
The simplest workaround is to cut larger projects into smaller, valuable work items. This means that stakeholders get some value more quickly (a small valuable part has been completed) and they can then get feedback or realize the benefits more quickly. And if one leader's priority is being actioned, another leader can wait patiently knowing their priority will be picked up once it’s complete, which should be in a reasonably short time.
6. Know your influence
Often, leaders are the culprits violating work-in-progress mandates. And usually, the violation is unintentional. How many times have you said something as seemingly innocent as, “I have this great idea that I’d love to do right now,” only to see your teams drop the important work they're supposed to be doing to follow you down a rabbit hole? So now, your team has even more work to do and less time to do it.
Here's another example. Have you ever sent an email to your team intending to inform them of something only to watch them take action? You didn’t want to generate any activity, but you’ve taken your influence – your authority – for granted.
Remember, all leaders have influence. It’s a given, and so it’s vital to keep this influence front of mind when communicating with your team. You must be explicit in your expectations – if you don’t want anyone to take action, say as much.
7. Cultivate psychological safety
What can your team members do if they feel their workload is over and above a manageable level for them? Imagine an employee comes to you and says, “I’ve got eight things on the go, but I want to limit work-in-progress to six. Can I drop these two projects?” You can’t shut down their concerns by appealing to your authority or stating, “That’s just a part of the job.” Leaders are responsible for encouraging these types of conversations by fostering a safe, easy, and open environment in which team members feel comfortable speaking up about their needs.
In addition, employees should have the confidence, support, and autonomy to map their own workflows and make decisions about their priorities. In most cases, frontline workers are closer to the inner workings of their projects than executives and other leaders. It’s crucial you trust your people to navigate their own way toward completion. In other words, you don’t want to push your agenda onto your employees, as you could be unknowingly sabotaging their plan.
8. Know when to start
Finally, encourage team members to refrain from starting a new project if they don’t have all the necessary information. This might involve establishing strong definitions of each stage of delivery. In other words, getting crystal clear about the parameters under which you and your employees can take work on. For example, you might list the milestones that must be met before teams move to the next stage of work. If these milestones aren’t satisfied, no one can push forward.
The goal is to ensure projects are seen through to completion without delays due to foreseeable dependencies not being met, so workers don’t end up with a pile of half-finished tasks in the system. These tie up capacity – not just in terms of actual work time but also the drain of thinking about them, sifting through higher quantities of information, and continuously prioritizing and re-prioritizing.
Get serious about WIP limits
WIP limits are game-changing. They enable higher productivity levels, limit context switching, reduce time to completion, and produce better-quality outputs. The value is evident, but implementation is not straightforward, particularly when you, as a leader, may be unknowingly adding more tasks to the table.
If you are ready to get serious about WIP limits and Agile more broadly, IncrementOne can help. We are Agile delivery experts and take a personalized and incremental approach to transformation. Agile truly is a mindset, and a successful transition demands change at the cultural level. We equip you and your teams with the tools needed to create higher-quality outcomes in fast-changing and increasingly complex business environments.
Schedule an appointment today, and let’s discuss your needs.