'93 or '94 KHS Team - buckled downtube. Probably my fault for hitting a Landrover wheel rut at 90 degrees at about 20 miles per.
Giant ATX 990 - pitting in downtube under paint (it blistered, I took the paint off to look, screamed and took it to the local Giant dealer, who got me a new triangle even 'though it was a second hand frame).
Marin (ech) Attack Trail. Frame was fine, but everything else blew up. Three SID air shocks, the travel adjust QR, the granny ring (god knows), every bottom bracket (It was ISIS) went after six weeks of riding. It was a real Friday bike. Should have bought the Orange Sub 5 I'd intended to buy in the first place.
Just to even things out, frames I bought that never, ever complained:
DeKerf Generation (Ten years going, now being ridden by a good friend)
Two Mountain Cycles San Andreaseseseses
Orange Sub 5
Commencal Meta 4