Baldur's Gate was the first PC game I ever played, beginning to end. My best friend and roommate played all sorts of games which I ignored. When I suddenly heard an NPC pipe up, "Gorion would be proud of you", I looked up from my book to ask what he was playing. I was hooked the moment I made my first character.
If it had been an MMO, my roommate wouldn't have bought it and I would have missed out on a great game.