Definition
The best-performing sample in the comparative analysis (compared to the worst-case-free-WOW).
In detail
Best of the Best (BOB) is the best-performing unit or batch within the same process, compared side by side with the Worst of the Worst (WOW) to find what causes the difference between them — it is not cross-plant benchmarking (see [[benchmarking]] for that). The output is a good-vs-bad comparison table and a list of root causes for the difference.
Example in practice
Within one process, some units in the same batch pass and some are defective. The team picks the best-performing unit (BOB) and the worst-performing one (WOW), and compares their raw material lot, operating technique, and equipment settings item by item to find the key variable causing the defect.