WIP constraints increase flow by forcing capacity matching. Which practice also helps improve flow when WIP is high?

• A. Time boxing
• B. Increasing local WIP pools
• C. Extending iteration length
• D. Reducing visibility of WIP

Answer: (A)

When WIP is high, creating a stable rhythm that caps work in progress is key to improving flow. Time boxing imposes a fixed time window for work, which enforces finishing work within that window and prevents new work from piling on top of it. This cadence forces smaller, more manageable chunks, reduces multi-tasking, and makes bottlenecks appear sooner, so teams can adapt quickly and keep flow moving. It also tightens predictability, since deliveries happen on a regular schedule within each box, helping align capacity with demand.

Increasing local WIP pools would add more work in flight, making context switching and queueing worse and slowing flow when WIP is already high. Extending iteration length tends to create bigger batches, which delays feedback and increases lead times, hurting flow. Reducing visibility of WIP hides problems and delays the response to bottlenecks, which also harms flow.