The bottleneck (or constraint) is the slowest station in the flow. It determines the throughput of the entire system. All the other stations, no matter how fast, can only serve at the constraint's pace.
The Five Focusing Steps
- Identify the constraint. The station with the longest queue in front is almost always it.
- Exploit it. Make sure the constraint is never idle - staffed at breaks, tooled correctly, protected from disruption.
- Subordinate everything else. Other stations run at the constraint's pace, not their own max. Otherwise WIP explodes.
- Elevate the constraint. Add capacity - more operators, better tooling, second shift.
- Repeat. Once elevated, the constraint moves somewhere else. Now that place is your focus.
Common trap
Optimising a non-bottleneck. If you make a non-bottleneck 20% faster, you get zero improvement in total throughput. All you've done is build more WIP in front of the actual constraint. Always attack the bottleneck first.
In MapVS
The bottleneck stage is highlighted in the analytics tab. If you're on the Pro plan and running DES, the simulation shows the constraint dynamically - which is useful because in a variable process the constraint sometimes moves.