Long ago I traded a beautiful 870 Wingmaster that I could hit anything with, for a Charles Daly SxS 12 Ga. It was a nice enough gun, made by Moruku, but when you pulled a certain trigger first (I can't remember which one) both barrels would fire. I traded it to a friend who said that didn't bother him. And later I replaced the 870.
There was a thread a while back that asked what the hardest recoiling guns you ever fired were, and I forgot to list that one.
Try as I might, I can't think of another one that I was unhappy with. There have been guns that I realized had no practical use, that I got rid of, but no others that I wanted to dump because of performance.
I was initially unhappy with my Marlin 1894, it would jam every single time you tried to run anything through it. I read up on it, and found out about the "dreaded Marlin jam". I ordered a new carrier from Brownells, then it worked just fine.