I don't think there's anything particularly magical about the number five. We weren't there and that may have been adequately deep analysis; we don't have the information to tell.

Personally, I can't say I'm inclined to think "the employee needs a table" is likely to have any useful root cause that goes any deeper... "I need a table" is hardly some sort of exotic need.

The whole episode is recounted from memory, not a transcript, so it's probably off a little. The real why answer is 'because he didn't have anywhere else to place objects in the work area'. The table is one solution. You could go another layer deep and wonder why the work area was designed without a stable horizontal work surface. Maybe the job duties changed, maybe the designers didn't know. At the fundamental level though, you've discovered a good corrective action.

I commented about this on the linked site and it was deleted.

Adding a table strikes me distinctly as ignoring the root of the problem, which probably has more to do with safety standards and training. There has to be a more robust way to prevent accidents than luring people away from them.

So, ironically, this seems to be an example of asking too many questions, and we're not even at 5 yet.

Actually, "luring" people away from accidents is often a better way than strict training. "Don't jay-walk across the freeway" will only work when a viable (and safe) crossing is close by. Otherwise your users will simply ignore your training to make their lives easier.

True, and I'm all for that kind of thinking in addition to common sense precautions. Maybe that was the case and there were huge signs and training manuals and off buttons all over the place but coderr's scenario sounds more likely.

My larger point is that failure analysis is complicated and full of red herrings. Simplifying it to "five whys" (or four, or six) only creates false security.

The "5 whys" don't need to be exactly 5; it's just the name for the process of getting to the root cause of a problem.

I suspect that there is a long tail of root causes when it comes to accidents. So a little more analysis of a number of cases might have led to a better conclusion.