Assassin's Creed
I've tried with three entries in the franchise. Black Flag, Odyssey and Valhalla. My main gripe is the bloat and repetitive copy paste approach to environments and locations. It has some good qualities, no doubt, put many hours into them, but I can't seem to finish them before I get bored.
First person shooters
I have a difficult time getting into these. I don't like the competitive nature of video games so I tend to dislike games like CoD and such but even when it's single player I just don't gel with these shooters. They bore me to tears. I think it's the generic war setting that push me away. The only FPS I can think of right now that I liked was Bulletstorm, the one with Duke Nukem in it, that game was very good. And hilarious to boot.