What films/shows disappointed you?
There's so many but the first that comes to mind for me is Amadeus. I love Mozart and I love Biopics but I hated this. It took me several attempts to get through it. I thought it was so dull and Mozart was utterly insufferable.(Probably the point but he annoyed me so much that I gave up.
Another is The Grand Budapest Hotel. I love Ralph Fiennes and I thought it looked funny and utterly charming but I really didn't enjoy it. Having tried a few other Wes Anderson films, I think that he just isn't for me.