Over here we're too proud to admit our mistakes, unlike you lot, but we still make them, in ten years of boating I've.....
Destroyed a guard rail my Bav 32 and a bow roller on anther boat in the marina (first time ever at helm, with an instructor)
Crunched the front of a Ben 21.7, thought I'd engaged reverse but hand't and slammed it in
Destroyed the prop and lower leg on my last engine by hitting the slip
and only last week I did my skeg as my brother had put the boat on the trailer and I hadn't noticed the leg was down.
I always sit on the starboard side when using an outboard tiller, that way the throttle will be like a bike throttle and the reflex will be to twist it away to shut off.