Work in progress limit
…a heap of work to be processed.
✣ ✣ ✣
Working on less items at the same time increases focus, reduces waste and lead times, increases throughput, flow and liquidity of the system, and triggers conversations about bottlenecks that surface.
work in progress limit brings extreme focus when tightened up.
If your wip limits don't hurt they're not wip limits, they're decorations.
Therefore:
Impose and uphold a limit on the work in progress at each state in the visual workflow to create a pull system in which individuals take responsibility. Tighten the limits until a bottleneck surfaces and turn it into a busy buffered bottleneck or collect them in the accelerator list. Put limits on swim lanes to balance work capacity. Leverage a cumulative flow diagram to proactively manage undesired behavior of the system. Encourage everyone to take responsibility, facilitated by the pull system. Repeat ad infinitum.
✣ ✣ ✣
✣ ✣ ✣
Maturity
Shu
work in progress limits are in place, yet need to be tightened up to discover key improvement areas.
Ha
A sophisticated, yet elegant use of work in progress limits govern the system as a whole, filling the accelerator list as they start hurting when tightened up, using scientific method and models.
Ri
Connecting parts of the ecosystem—both internal and external—ask you to help them set up a similar, pull-based system with explicit policy and a crystal clear interface and protocol at the boundaries.