Oh hey, we shitting on One Piece in here?
Personally, I just thought it was boring. I read the manga when Shonen Jump came out and found the art style off-putting, but I could maybe get over that or it could grow on me. Then the main character ends up being dumb as a rock, stabs himself in the face, and becomes super stretchy. Anything interesting that popped up couldn't make up how ugly and tropey it was. And by the time Luffy pulled a sharkman's teeth out to use against him, I was done. I tried watching the anime, but it moving at a snail's pace did nothing relieve the boredom I felt reading the manga.