The Bottleneck

In any production system, one station determines the maximum output of the entire line — not the fastest station, not the average, but the slowest. Goldratt's Theory of Constraints calls this the bottleneck: every unit the line produces must pass through it, so its rate caps everyone else. Investing in any non-bottleneck station does not increase throughput — it only builds inventory in front of the constraint and wastes capital. Before spending on capacity, you must identify which station actually limits the system.