Lots of movies which I have, thankfully, forgotten.
One that comes to mind is: Lost in Translation (2003)
Bill Murray and Scarlett Johansson are feeling lost and disconnected in the alien Japanese culture. This goes on for an eternity while I felt lost and disconnected from the movie. But it has a high rating on IMDb, so it must get better along the way, right?... Wrong!
This is the usual reason for me wasting time with a movie; the presumption that what a lot of other people like will also be something that I'll enjoy myself, or if it wins an Oscar it must be worth seeing.