I don't do mishaps, I have God hates me days.
Just laid a new carpet, trying out the new airbrush, filled up the cup and pressed the trigger to get the air pressure - forgot to put the needle back in.... Luckily the carpet was in my hobby room.
Went up to the shed to do some spraying, ran the extension lead out, plugged the plug into the wall socket, forgot to turn on the electric so it was all the way back to the wall socket, took the plug out, re-wound the extension and put it away then could not work out why the compressor was not working....
Finished one of my builds then realised I had put the tracks on backwards...
Went looking for a Challenger 1 model that I had put away in a Challenger 2 box, went back and forth looking, checked the bins, up into the attic, up to the shed, into the spare room cupboard. Spent hours clearing out shelves, cupboards, moved all the boxes from under the bench, no sign of it. Convinced I had put it in the recycle bin weeks before I settled for second place and got out the Challenger 2 - looked at the box top and there written in Sharpie pen black letters 'Challenger 1 - needs track'.....
Or how about in the attic sorting out the stash, in model making dream world, wife comes along and moves the ladder out of the way unknown to me, then goes out to the shops....