I suspect that this is because a human propensity exists to allocate and apportion blame, particularly in cases where the interactions involved in the immediately prior actions are unclear.
I have actually not even once encountered this 5 Why's method.
I neither heard of it before.
But I founded my company in 1996, starting out with almost two hundred years of experience surrounding my incredulous and lucky younger self, including several PhDs and former Fortune 500 board members.
I will hazard that this 5whys technique is fundamentally flawed and easily susceptible to manipulation for procuring a scapegoat.
I only hope that explains why I have never encountered this before. I hope moreso I can feel a little like somethingwas going on in the right way, in my business, to filter and reject what I think is, and definitely comes across as bogus to me.
However, 5-whys is very useful as a design principle instead of using it to respond to failure.
It goes something like:
0: build a thing why 1: because customer asked why 2: because thing is what they think they need why 3: because it is one solution to a gap in their ability to achieve something. why 4: because that something is an economic need. why 5: because market opportunity to fill that gap with something, maybe this thing, maybe something better.