Jogging my memory, I just came up with two for this:

Dead Ringers: First time I watched this I was disappointed it wasn’t a special-effects, sci-fi horror classic like Videodrome or The Fly. I watched it later and appreciated its twisted eroto-gynocological black humor.

Miami Vice: Expected more from it when I saw it in the theater — I’m a huge Michael Mann fan — plus the abomination of a greasy mullet clad Colin Farrell replacing peak-80s Don Johnson was just offensive. I watched it later and appreciated it as a great crappy action-movie, basically a Michael Bay flick made by Michael Mann.