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.