“Why” is about purpose; “How” is about mechanism.

I have been annoyed with what seems to be either a lazy or deliberate misunderstanding of both the context and actual meaning of “5 whys”. However, the point of “root cause analysis” is to understand mechanism. Understanding mechanism allows for intervention, at multiple points if needed, to produce an outcome you prefer. So from that perspective, “why” isn’t the best way to express the intention. “Why” is really about understanding purpose; “How” is a better word to convey understanding mechanism.