Hmm I've played quite a few bad games but if I were to think of some
Sonic Spinball - Genuinely miserable to play, controls were ass, music was ass, only beat cause I was on an emulator
Bubsy 3D - Textbook example on how not to make a platformer. It's true when people say the entire game looks like an unfinished alpha build. Controls are fucking clunky, camera is ass, Bubsy's voice is fucking annoying, music is ass. I think I stopped playing around the water levels.
Major/Minor - Furry visual novel I played in high school. No skip system, only can save when the game stated you could and im pretty sure it was made in RPG maker of all things, all the cast had one sprite only, reeked of writing by someone who had no clue what Japan was outside of anime, and all the characters had only a singular smiling sprite. Dropped after the ch1 demo.
Dragon Slayer - I respect it from a historical context and how it brought Falcom to where they are now, but from a modern day perspective it's genuinely just fucking boring and a slog.