What are some games you feel had great potential, but never really got to be a great game?

For me it would have to be the first Crysis game. I can't believe how so many people will never experience the amazing fun that the multiplayer actually was. After release, me and a couple of friends started playing the multiplayer. Coming from playing competitive BF2, we grasped it pretty quick, everything except the nano-suit. When we finally were able to master the nano-suit, HOLY SHIT that was some of the most fun I've ever had in a multiplayer game. EVER.

I also really liked the objective-based maps(the maps in general, really), and the upgrade-system for weapons.

Then the hackers started invading it. And the bugfixes never arrived. And the development shifted over to making an expansion/new game. It got stale and broken. These things, and also the high PC requirements, I believe is what kept this game from reaching its full potential.

Not to mention the singleplayer. If it was a tad less linear and more free, it would have been close to perfect. There was still so much you could do with the suit, though. Want to stealth behind a building, jump to the roof, beat a hole in the roof, and smack the guys hiding in there to death? Sure. Stealth -> Strength. Maybe throw a grenade in there for the whole experience. The difficulty could also get really challenging if you decided to crank it up. And everything was so beautiful. Experiencing the DX10 lights on ultra for the first time... My god. I still play through it almost every year, although I've been lazy so far this year.

Everything I say is of course my opinion. What's yours?