Half-Life 3 syndrome 

A phenomenon that occurs when a piece of media (mostly video games) is put on hiatus or when there is a very large gap inbetween releases, where people will overhype and praise the content to the high heavens, even before release. It then either doesn't get released or does get released, causing everyone to be disappointed because their soaring expectations weren't met, that weren't very realistic in the first place.

This isn't the doings of the developers, this is the doing of the community who in an attempt to keep their hopes up, make excuses about their favorite piece of media being or soon becoming the greatest piece of entertainement ever, e.g. Half Life 3. Aforementioned hopes are then usually crushed and they go to metacritic to rate the item a flat 1 or 2.

Adam: ''My god, Duke Nukem Forever sucked!''
James: ''It was overhyped to all-hell and in development for like 10 years, ofcourse you were going to be let down.''
Adam: ''Classic case of Half-Life 3 syndrome.''

Half-Life 3 syndrome by Pillium December 25, 2013