Constraint

Any resource, policy or condition that limits the throughput of the overall system.

Examples

01The value-stream team finds that the heat-treatment furnace is the constraint: every other step could produce 20 % more.
02The team checks the constraint at the gemba and sees parts queuing for 3 days in front of the furnace, which no system report showed.
03Before adding a second furnace, the team tests running the constraint through breaks and measures the effect on lead time and WIP.