Index

Mental Models

Bottleneck

A bottleneck is the single constraint that limits the maximum throughput or output of a system at any given time.

Identifying bottlenecks prevents wasted optimization on non-constraining parts of a system.

Core question

What is the one constraint that, if relieved, would unlock the most capacity?

Example

A product team ships features fast but growth stalls. The bottleneck is not engineering speed — it is distribution. No amount of feature work helps until the distribution constraint is addressed.

How to apply

  1. 1.Map the full process from input to output.
  2. 2.Measure throughput at each stage to find where work accumulates.
  3. 3.Focus improvement effort on the bottleneck stage only.
  4. 4.After relieving one bottleneck, find the next one — it always shifts.

Pitfalls

  • ·Optimizing a stage that is not the bottleneck, which yields zero system improvement.
  • ·Assuming the bottleneck is permanent — it moves as the system changes.
  • ·Confusing a slow stage with the actual constraint; slowness only matters if it limits total output.

Questions

How do you find the bottleneck in a business process?

Look for where work queues up. The stage with the longest wait time or the largest backlog is usually the bottleneck.

Can there be more than one bottleneck?

At any moment, one constraint is binding. But relieving it reveals the next. Systems always have a bottleneck somewhere.

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