I am constantly amazed when conversations about safety devolve into conversations about statistics. Not that I have any problem with statistics. All you statisticians out there can relax. There are a million things that could be discussed in which statistics could play a solid role. I just happen to feel that when it comes to shop safety, statistics are meaningless. It simply does not matter how many times out of how many times someone gets whacked while performing a particular operation.
The way I see it it's kind of like tossing a coin. Every time you toss the coin, the odds of heads or tails are 50-50. You can toss the coin a million times and on the million and first time, the odds are going to be 50-50 no matter how many times it was heads or tails the million times prior. I once tossed heads 11 times in a row. I was with a group of friends and one guy kept saying "double or nothing" and then I would toss the coin again and it would come up heads! The odds of this happening 11 times in a row are astronomical. It's really too bad we were not betting "real money" because I could have cleaned this guy's clock. If we had gone in with a bet that I could toss 11 heads in a row, I could have gotten huge odds on that bet. But the odds on each toss were exactly even. 50-50. Every time.
To me it does not matter how many times a guy performs an operation without getting injured. The chances of getting injured are exactly the same every time. Thinking that you are safer because you have done something a million times without being injured is foolish thinking. The biggest cause of injury is overconfidence. And overconfidence grows out of trusting statistics.