I think what often determins favourites is the order you experience new game mechanics in. For instance, I enjoy Banjo Tooie & dk64 on n64, but i felt underwhelmed & felt things were usually too easy, because I had learned the mechanics from super mario 64 & banjo kazooie, thus why they didn't become favourites. If I had played those 2 games first, It would possibly be the other way around. I think that is a huge factor in people's enjoyment of certain games. Popular (and probably great) Games like Fallout 3 can be utterly boring and feel like nothing new depending on what you have & haven't experienced in your years. I think an important factor for a game to be addictive, is for it to create a sense of wonder. Wonder of the mechanics, how things work. If the patterns all look too predictable from the start, the odds of it being fun are less likely. Learn too much, and alot of the great games that come out offer you nothing, they're dull. Minecraft/Terraria/DoD/Super Meat Boy have been the biggest innovations (atleast for me) in the last couple of years.