Personally there are a few games which left me very dissappointed, after hyping myself up for years in certain cases.
Divinity Original Sin: turns out I prefer more streamlined, less packed games (love Pillars of Eternity) and that coop play in a CRPG stresses me out.
Wasteland 2: I actually managed to finish this one but secretly I admit I was hoping for a better Fallout which I didn’t really get. New Vegas did the cowboy theme much better.
INSIDE: while the design was cool, it was just a ton of boring, easy puzzles in comparison to LIMBO, its predecessor.
Ah, seconding ark. I wanted a couple weeks after my friends jumped aboard the hype train, which lasted only a short couple weeks. A few years later and it’s free on EGS, a friend of mine owns a steam copy, and we cannot for our lives manage to connect a private game server between the two platforms. Basically first and one of the very few games I’ve ever refunded on steam, and not even worth playing for free from EGS.