I have never caused any insurance claims, thankfully.

Recently, We were mounting a TV over a fireplace. We had previously mounted a TV in the same house over the same fireplace for a previous owner with no incident. This was a different TV and different mount and different owner. Homeowner was helpful enough to have measured out where the mount he bought needed to be mounted to locate the TV where he wanted it. So I went to drill for the lags. 2" in, and I got a spark, a bit of smoke, and popped the circuit.

Framers used 2x4 "sideways" to frame above the fireplace. Electrician stapled romex directly to the backside of the sideways 2x4, likely just a single staple next to the box. I got lucky enough that that ~3/4" area happened to be right where the lag needed to go. I moved the drill an inch and missed the romex. Mounted the TV, turned the breaker back on, and everything was ok.

I had a co-worker once who was preparing to cut some in-wall speakers into a garage soffit. It was sheetrock over OSB. So he needed to drill a pilot hole to get the saw in there. For some reason, he grabbed the longest 1" auger he could find. It was dull. So he was using all his weight to push it through. It went through alright. All ~16" of it....at high speed. Right into the 000 feeder for the electrical panel. Huge spark, and LOTS of smoke out of that 1" hole. He panicked and ran in to find the homeowner, and asked for a "fire extinguisher or a cup of water".....that is a direct quote. I was not on site unfortunately. I would have died....from laughing so hard.