This isn't really about best games or how good games are but more how they stand out from a technological point of view and create new standards, or just stand out for whatever reason.

I'm not going to debate god of war isn't a great game, and I have doubted many times to put it in there. But apart from being a great game I can't really see a reason for it, and to put all great games in there for 45 years, I would need a lot more room.