If we're going the hypothetical route on games that have yet to be released then pretty much all games have a potential to be disappointing.
We're talking biggest disappointment though. If Far Cry 4 comes out and is garbage it will be far more devastating for this website than if say Dragon Age or Assassin's Creed turn out bad.
So it's really what games GB is most excited for/anticipating which will turn out to be really bad or mediocre? Is there any one game, besides maybe Farcry 4, that the entire GB staff is unanimously excited for that is worthy of being (potentially) called Most Disappointing Game of 2014?
Evolve was delayed, that would've had potential. Otherwise, I can't say for certain which games the majority of them are looking forward to this year. They seem to be favoring Sunset Overdrive and Alien Isolation a bit, but nothing like for Far Cry
I'd really like Far Cry 4 to be really good, but I hope for something more for GOTY. Obviously thats the fault of having more sequels over new ip's, but it almost feels like Far Cry 4 would win by default.
Who knows, maybe the upcoming games I listed as possible most disappointing could end up being GOTY. Alien Isolation taking it by surprise would be fresh, especially considering the situation the Alien brand was in last year in video games.
Shadow of Mordor would be really great for Monolith; I'm afraid if it bombs Monolith might be made no more, and we need a new FPS from them dangit!
I don't think they even had high expectations for Destiny; they were curious as to what it even was and when they did finally find out it was them playing the Alpha. Unless they talked about it during bombcasts, I'm ignorant in that aspect.
Same with Watch Dogs, they didn't seem to be hugely disappointed and agreed it was a competent video game.
I have a feeling the most disappointing will be a game not yet released this year; maybe Sunset Overdrive (I hope this ends up good) Alien Isolation, or god forbid Far Cry 4