I rarely buy games as soon as they're released unless I'm sure as hell I'm going to like them. This usually only applies to sequels of other games I loved.
But, I've been trying to force myself into the stealth game genre for ages and I just couldn't seem to like any I played. I tried every MGS game except 4, I tried Thief, Hitman, etc. I just didn't like them.
Then Splinter Cell: Conviction came out and I read a few reviews. They all said it was a great game with a unique take on stealth, wherein the game would reward me for patiently slipping by enemies, setting up careful traps etc, but where it would almost always be possible to shoot my way out if caught. I thought this would be a great place to start, so I went to the store and put down full price for it.
Turns out I was right: it was a great place to start. I loved the game, I enjoyed the plot and had fun experimenting with various stealth techniques. But the single player was just over too soon, and still managed to repeat itself a bit. The multiplayer wasn't much good, and it died off very quickly. All in all, I wouldn't have regretted buying it at all if I'd paid $30 or less for it, but at $60 I was quite disappointed.