It's a little old but here's a quick opinion piece via eGamer.co.za about why such games as Rage, Final Fantasy XIII and even Crysis 2 in the minds of some, are bad games. Spoiler alert: They're tech demos.
"Is bad the right word to use? Perhaps. It’s definitely the easiest in a pinch, especially when you’re finding difficulty placing such games. It certainly isn’t too harsh of a criticism while remaining on the side of judgement that you’d like to place the games in question, wherein you are in fact saying the following: They’re shit. "