Never had a disaster, once going to Lake Chautauqua in New York for a tournament the trailer came unhitched from my buddies truck, it just bumped his bumper though. My boat and trailer and he hooked it up, when I did it I cranked the leg down and applied pressure to make sure it was hooked up good, he didn't.
My buddy and his son took me fishing to a lake 70-75 miles away, I am disabled and only could handle a 30 - 45 minutes in the boat, I told them to just take me back to the ramp and I would sleep in the truck. Probably a good thing, I was walking past their trailer and notice 2 or 3 cross beams on their trailer had broken welds, and they were leaving for a trip to the French River the next weekend. They got it fixed before they left, a long way to travel with a glass bass boat with a 150 on the back.
A buddy lost an almost new Nitro on I-90 coming back from New York. Can't recall even having a flat on a trailer tire myself. Either lucky or alert? I tried to avoid hassles.