That's why I always check trailer hitch (gooseneck or bumper) and wiring connections with a fine tooth comb. Actually saved myself from a disaster yesterday. A new guy who works for the broker was going to cross the border with our animals loaded on a bumper pull. Checked his truck out of habit and he hadn't even bothered to secure the coupler properly or install a safety pin. Would have been on the hook for 18 whitetails plus whatever other mayhem the trailer did. Ripped into him for being a Dumb Azz. @thebravo is right the gal standing there has a death wish.