What Is Bottleneck Analysis?
A bottleneck is the slowest step in your process that limits overall output. Learn how to find and fix bottlenecks systematically.
Key Takeaways
- A bottleneck is the process step with the lowest capacity, which limits the output of the entire system.
- Improving any step that is not the bottleneck will not increase overall throughput.
- Identifying and resolving bottlenecks is the fastest path to increasing output without adding resources.
What a bottleneck is
In any multi-step process, the bottleneck is the step that processes work the slowest, creating a queue upstream and starving steps downstream. If your factory can cut 100 units per hour, assemble 60, and pack 120, assembly is your bottleneck. Your factory output is capped at 60 units per hour regardless of how fast cutting or packing operates.
How to identify bottlenecks
Look for work-in-progress accumulating before a step. Measure the cycle time of each step and compare them. The step with the longest cycle time relative to demand is typically the bottleneck. In service businesses, bottlenecks often appear as approval delays, overloaded team members, or handoff points where work waits for the next person to be available.
The Theory of Constraints approach
Eliyahu Goldratt's Theory of Constraints provides a five-step method: identify the constraint, exploit it fully, subordinate all other steps to it, elevate the constraint's capacity, and repeat. A South African textile manufacturer used this approach to increase output by 35 percent simply by reorganising shifts to keep the dyeing process running continuously.
Shifting bottlenecks
Fixing one bottleneck often reveals the next. This is expected and healthy. Each time you resolve the current constraint, overall capacity increases until a new step becomes the limiting factor. The discipline is to always know where your current bottleneck is and focus improvement efforts there, rather than spreading resources across every step equally.