Why does limiting WIP matters ?

An application of Little’s Law

For those of you using Scrum, Scrumban or just Kanban, you might be wondering why it matters to limit the Work In Progress (WIP) in a given queue.

Little’s Law
  • Increasing the throughput
  • the number of CPU’s in a server
  • the number of hours in a working day

Other benefits of reducing WIP

Besides reducing cycle time, reducing WIP gives a team the following additional benefits:

  • Increased feedback: faster feedback on items delivered to customers
  • Less overload: items don’t pile up in a queue, but transition smoothly from left to right on your planning board
  • Increased quality: faster feedback in combination with adaptive teams will make the teams produce with a higher level of quality

The main goal of an agile team…

… is to get things done. Reducing WIP will give you the ideal setup to accomplish this goal. It avoids that items are clogging up your queues and, by consequence, avoids that people in the team are facing a backlog too big for them to handle.

The max WIP is 4 items, so the developers can not push any more tasks on the ‘test’ queue. Instead, they should help the testers to get tasks moved to the ‘done’ queue.

References

Little’s Law: http://en.wikipedia.org/wiki/Little's_law

Enterprise & Solutions Architect consultant.

Enterprise & Solutions Architect consultant.