Outstanding post over at the Evolving Excellence Blog:
Lowering The Water Level
Toyota calls it “lowering the water level.”
Imagine a value stream or a production process as a river. Reducing the inventory in the process – “lowering the water level” – exposes the “rocks” that represent all of the hidden costs and waste in production. Only by revealing those rocks can you improve the process and reduce the waste.
This metaphor works for knowledge workers, too. In this case, however, their key inventory item is time. Having too much time to do one’s work hides the waste and inefficiencies in the process.