> every system has exactly one bottleneck at any given point in time.
Consider this system that has 5 sequential steps with these durations:
Step 1: 10 seconds
Step 2: 5 hours
Step 3: 7 seconds
Step 4: 5 hours
Step 5: 18 seconds
It would seem that both step 2 and step 4 are both bottlenecks. Are you saying that in reality one of those 2 steps would not typically be the exact duration so one of them would be considered the actual bottleneck?
In this example, assuming sequential steps, if step 2 must be performed before step 4, then it is step 2 which is the bottleneck.
After step 2 has been optimized, step 4 becomes the new bottleneck—assuming that optimization of step 2 is satisfactory.
While both steps 2 and 4 contribute to a slow system, a bottleneck means something else entirely: it is the single most significant point of slow down for the rest of the process.
To put it another way, it’s hindering the overall execution. If both use the same amount of time, then whichever is closer to the front of the process is by definition hindering more of the process.
Consider this system that has 5 sequential steps with these durations:
Step 1: 10 seconds
Step 2: 5 hours
Step 3: 7 seconds
Step 4: 5 hours
Step 5: 18 seconds
It would seem that both step 2 and step 4 are both bottlenecks. Are you saying that in reality one of those 2 steps would not typically be the exact duration so one of them would be considered the actual bottleneck?