Too busy to read?

WIP is a leading indicator of cycle time. The more items that are worked on at the same time, the more doors open up that allow dependencies and interruptions to creep in.

WIP: All discrete units of customer value that have entered a given process but have not exited.

Thief Too-Much-WIP is stealing time from you when: Context switching is common: When computers context switch, the state of the process currently being executed is saved so that when it is rescheduled, the state can be restored to its correct spot. Because computers perform hundreds of context switches per second, it's easy to believe that multiple tasks are performed in parallel, when in reality the central processing unit (CPU) is actually alternating or rotating between tasks at high speed.

The odds of being predictable decrease when WIP constantly in-creases and flow times elongate. Remember--WIP is a measure of how many different things are being juggled at the same time. Unlike most other metrics, WIP is a leading indicator. The more WIP there is in the pipeline, the longer things take to complete, period.

Little's Law to understand the math behind why WIP extends completion times. Recall that lead time equals WIP over throughput. Given WIP is the numerator of that fraction, we know that when WIP goes up, so does lead time.

"Everyone knows that in manufacturing, as wip increases, due-date performance goes down.

"In the 1980s, this plant was the beneficiary of three incredible scientifically-grounded management movements. You've probably heard of them: the Theory of Constraints, Lean production or the Toyota Production System, and Total Quality Management. Although each movement started in different places, they all agree on one thing: wip is the silent killer. Therefore, one of the most critical mechanisms in the management of any plant is job and materials release. Without it, you can't control wip."

Work-in-progress and cycle time have a relationship. High WIP means that other items sit idle, waiting for attention longer.

Context switching, which wastes time, is a major consequence of too much WIP.