How to Set WIP Limits on Your Columns When You’re Just Getting Started
Limiting work in progress is a commonly-used activity practiced by countless Agile teams. And it is the most effective tool you could possibly use to create a strong, clear focus for your team and dramatically improve your delivery speed. However, when you’re just getting started, it can be challenging to determine how to set WIP limits on each column of your Kanban board.
Unfortunately, there is no universal formula that will help you set the limit of the amount of work that is allowed to exist in each column at any one time. The truth is, whatever your initial limit per column is, most probably you’ll be wrong. The best you can do is to make an educated guess. The most important part of this process is to start with a rough figure and keep adjusting it over time.
Even though there isn’t a precise equation you can use to calculate your WIP limits, today, I’d like to give you some actionable advice that will help you head in the right direction.
Columns Represent the Activities in Your Workflow
Let’s start with the basics. Your workflow represents the knowledge discovery process and as such it consists of activities. The columns on your Kanban board represent these activities. Your columns are not containers for specialties, departments or working environments. They depict how the team members collaborate with each other to get the work done.
So, when we set WIP limits per column, we limit the amount of work items per activity and different people are able to fill up the slots available in each activity. Always remember that, in Kanban, we manage the work, not the workers. In Kanban, we let the workers self-organize around the work.
Let Your Team Set Their WIP Limits
Let’s explore an approach to setting WIP limits that will give you a solid starting point.
First of all, it is the team that should decide on the limit of the amount of work they are handling, based on what they understand of their capability. Don’t fall into the trap of dictating the WIP limits for them. Instead, ask them. If the team members are the ones who set their WIP limits, there won’t be a reason to break them.
Gather the whole team and discuss the activities they are contributing to. Go around and ask everybody “What’s the number of things you could do at one time and still stay at your happy place?”. For engineering personalities, that number will be much lower – it could be 1 or 2 – and for more creative people, that number can be higher.
While having this conversation, you will learn more about your team and the way they work. Even though the goal is to have people do less at any one time, it shouldn’t come at the expense of the team’s happiness. Think about what the happy place for your team is.
Take All Perspectives into Consideration
Even though the number of people plays a role, we want to manage the work itself. When you do the math, consider the number of people per activity and the amount of work each of them said they can handle.
There might be people working across multiple columns. Let’s say you have a Development column and Code Review column, and a developer can work in both these columns. If that’s the case, split the WIP limit of this engineer between the columns. So, if their sweet spot is to work on 2 items at a time, allocate a WIP limit of 1 to both the Development and Code Review columns.
Make sure you’re reducing the WIP limits per activity to the point at which you increase flow and drive a positive impact on quality while keeping your team members motivated and engaged.
It’s OK to Adjust Your WIP Limits
I often get asked: “Once we set our initial WIP limits, can we change them afterward?“. Absolutely. You can change your WIP limits as often as you need. Well, don’t do that on a daily basis, otherwise, they will diminish in value.
I’d argue though, that the more important question here is, “How often should we change our WIP limits?”. And the answer depends on whether going down this path comes from the right motivation.
If you increase your WIP limits due to high demand, that will ultimately slow you down. Based on Little’s Law, with an increase of WIP, your cycle times will also increase. So, when you consider changing your WIP limits, always make sure that the demand still aligns with your team’s capability.
It would probably make sense to change your limits if your circumstances change. If you have a team member on a vacation for an extended period of time (say a few weeks), if you involve a new member or you lose a member of the team, you should probably consider changing your WIP limits.
And by all means, don’t increase your WIP limits just because people in certain activities work faster than others. Regardless of how efficient some workers are, at the end of the day, they can still only process one thing at a time.
Start from one place and keep your limits the same for a while. That way, you can understand whether the assumption you’ve made improved your performance.
Observe how the trends of your flow metrics build over time and keep experimenting. As long as your cycle times decrease, your throughput increases and your teammates feel motivated and happy, you’ve been doing it right!
If you’re interested to learn more about how to manage your work effectively and develop a consistent predictable delivery workflow, I’d be thrilled to welcome you to our Sustainable Predictability program.
Meet the Author
Sonya Siderova is a passionate product manager and a driving force behind Nave, a Kanban analytics suite that helps teams improve their delivery speed through data-driven decision making. When she's not catering to her two little ones, you might find Sonya absorbed in a good heavyweight boxing match or behind a screen crafting a new blog post.