Work In Process (WIP) is a simple concept. The simplest definition of WIP is any piece of work started and that isn’t complete. It does not matter whether it is being worked on or waiting for a decision or the next step in the process. If a team pulls two pieces of work and starts working only to discover that they need to have a meeting in a week to decide on a course of action, they both are still WIP even if nothing much is going on until the meeting. One of the bumper sticker sayings that define agile is that teams should “stop starting and start finishing”. The basic meaning is that starting too many pieces of work causes teams to finish less work than they should. Having too much WIP has all sorts of implications. A straightforward implication is that the higher the WIP a team has the more time they will spend switching between work items. That means more thrashing occurs. The linear relationship between increased WIP and increased context switching is true for teams, organizations, and individuals. I have always struggled with moderating my own WIP. I like saying yes. I adopted the idea of a 5 item shortlist when I read Monotasking by Staffan Nöteberg (check out my re-read of Chapter 2, Cut Down on Tasks to Do). The shortlist helps control my WIP by throttling work entry. It has been a huge impact by reducing the number of items on my active to-do list that I am ignoring. Less WIP means less neglected WIP, less cognitive load worrying about the work I am ignoring, and more things done at the end of the day. Work that has started and waiting while teams pull other work generates neglected WIP.

Work that has been started and is now just sitting around is neglected. Running a team or organization above their natural level WIP for any length of time causes flow velocity (throughput) to slow and flow time (cycle time) to increase. When there is too much work, people try all sorts of techniques to get work done. Multitasking is the grandfather of them all and we all know how that turns out (need a hint – badly). In the end, all approaches to trying to do too much work ends up with some things being juggled and ignored. That is neglected WIP.

This is a harbinger of missed commitments and trust problems. Right or wrong, when you tell someone you have begun their work they begin to expect the completion; when work drags on or completion doesn’t happen trust and satisfaction wane. Following the chain of events further, it is easy to expect increased levels of stress and turnover yielding a death spiral. Finding a way to identify when WIP tips over into churn and neglect is critical.

Being able to know where the line between the right amount of WIP that provides the best flow of value and a death spiral of inefficiency is not easy but possible. As humans, we are phenomenally good at rationalizing our behavior until we can’t. Enter metrics to facilitate the discussion. Neglected WIP can be calculated if you understand Little’s Law and know your flow time and flow velocity. Little’s Law allows a team to estimate the WIP they should have (a great approach to setting an initial WIP limit). The equation for neglected WIP is Actual Flow Load – Predicted Flow Load divided by Actual Flow Load. If flow load is a foriegn term, think WIP. .

I had a friend in high school who rebuilt cars for stock car racing. I remember him discussing the impact of running engines “hot”. Michael V once (and only once) demonstrated to me on a back road that you could hit 130 miles per hour for a short period of time by red lining a car. He also went on to prove that running the car too long at that speed meant that you had to walk home and listen to a lot of swearing along the way. Teams are no different. Teams can run hot for a bit but only a bit. Too much WIP causes a myriad of problems. As coaches, we can help the team develop a line that you shouldn’t cross.

Next a short case study to illustrate the calculations.