Just passed my mind - games can actually be compared quite well to movies. Bear with me:
Blockbuster games. These are .. shallow games, they are not bad per se, but they lack longevity. Maybe they got popular because of cutting edge graphics or because they were popular genre. I classify lots of FPS in here, you have fun playing em (ok, I don't), but you rarely, if ever return to them. Their only remedying quality is usually multiplayer. Just like blockbuster movie - you don't want to see it again, and if you do its because you go there with friends. Anyone played Doom 3 lately? Yeah.
Cult movie games. They never get hyped, nor they get overly popular or become matter of flame wars of gaming forums, but somehow, you cant get em from your system. Graphic can be crappy when you return to them, but you do return, because they are simply fun. Years later, games that came out same year which boasted about having better shadows or something like that are forgotten, but cult games still get played.
Soap opera MMOG. It's just majority of such games as of now. Its name kinda explains it, if males playing them became housewives, Soap operas would fill blank in then just like grinder mmog fill blank in them now. These games run fast out of interesting content and get stale, you still have tons of stuff to do, but its no longer interesting, challenging or intriguing enough to really satisfy you, instead they give you idea that you want bigger number somewhere ... just like soap opera runs out of interesting stuff to watch after few episodes and then it is based on repetition and giving viewers (players) more of same, sometimes with cliffhanger (only one hour grinding till my rank in something increases, episode ending with "it was my evil twin, Rodrigues all the time!"). You have little room for creativity - you are getting content to be consumed, not to be enjoyed, and you are getting it without vitamins so that you have to mindlessly consume lots of it.
Quality series MMOG (think of Firefly). It runs short, but its worth it, its intense, interesting, fresh, short. By time you would be bored with it, you run out of content. Here is greatest flaw: Player expects it to become soap opera at that time, he wants artificially prolong lifespan of game for him, but its not possible. Why? Because adding grind would not prolong enjoyment, it would only prolong players time in game. What player has to realize is that he is supposed to put game down, find another one, and have fun there.
This page is shamelessly optimized for firefox, if you could stand my rambling, you can stand that.