Okay, here goes my first one from about 35 years ago. This has more to do with respect, then dumbness, but now that I look back, it was pretty frickin' dumb.
Had used all kinds of power tools and had my own.... and in the beginning got by, by making do with what I had. Landed a nice job, which needed many many pieces of wood cut into smaller pieces, so I put the cost of a nice new table saw into the quote. Got the job, so I got the saw. They delivered it and even set it up for me. So, I was experimenting, cause everything I did so far had been with a straight edge and a circular saw. So, I was cutting a piece of wood, running it along the fence with my miter gauge and I musta gone a little crooked.... as a piece shot out the back of the saw, hit me square in the stomach, bounced across the room about 45' and ricocheted off that wall and traveled another 80' out through a window at the other end of the building. I couldn't believe how fast, far and furious that thing went. Then........ I felt my stomach under my shirt. Pulled my hand out and it was a bloody mess. I felt around and felt a deep hole. I thought, oh no, my guts are gonna pour out in a second as this thing opens up more and more. I felt around some more but couldn't feel my hand as I was so numb in seconds, I thought I was gonna die on the spot. Then I thought, why ain't I falling over ?? Here, I didn't put a hole in my stomach, but the point/corner of the wood hit me dead on in the belly button and tore open some skin and while I was bleeding, it was just a surface wound and not a penetrating wound into my guts. Closed up shop, went home, showed my wife and she said.... Looks like another close one. You better be more careful. She's still saying that, to this day. Ya just never learn. You can tell people what to do and how to act, but ya never listen to your own advice..... not usually. Can I get a witness ??