Definition
A bottleneck is the resource, activity or process step whose limited capacity restricts the overall throughput of the system.
Human Explanation
A bottleneck determines how much work the entire system can complete. Improving non-bottleneck activities rarely increases total output.
Why it Matters
Recognising bottlenecks allows organisations to prioritise improvement where it delivers the greatest operational impact.
Conceptual Boundary
Every bottleneck is a constraint, but not every constraint is necessarily a bottleneck.
Practical Perspective
Improving the bottleneck almost always has a greater effect than improving already underutilised resources.