Definition
The worst performing sample in the comparative analysis (compared to the best BOB).
In detail
Worst of the Worst (WOW) is the piece/batch with the worst performance in the same process or operation, compared in pairs with Best of the Best (BOB) to identify where the two differ and what factors caused the gap; it is not the opposite of "benchmarking" (BOB is also not benchmarking; see [[bob]]). The usual outputs are a WOW list, root cause analysis report, and improvement recommendations.
Example in practice
Within the same batch of products from a process, the team selects the worst-performing piece (WOW) and the best-performing piece (BOB), compares raw material batch, operating method, and equipment parameters item by item, and identifies the key difference that caused this piece to deteriorate, then makes improvements.