In Eliyahu M. Goldratt's 'Theory of Constraints', you can't ...

In Eliyahu M. Goldratt’s “Theory of Constraints”, you can’t increase the throughput of a factory by making each step in the manufacturing process faster.

That only results in building up inventory which actually decreases the efficiency of the entire process.

Instead, identify and fix the biggest bottleneck. Even if you do that inefficiently, with more labor, or with a sub-optimal machine, fixing the biggest bottleneck increases total throughput.

Once that’s done, then focus on the biggest bottleneck of the newly revised process.

The counterintuitive result is that by focusing only on constraints, the process steps that are unconstrained will be idle much of the time.

Inexperienced factory managers see people standing around doing nothing and think this is inefficiency to be eliminated. Experienced managers realize that idleness is essential at unconstrained stations, and trying to eliminate it will actually decrease total output.

Optimize for throughout (of the system), not latency (of every component).