On a personal level I look at hours played vs $$$ spent. If I'm getting better than $1/hour, then the games been good value for me.

I am also an achievement hunter though, so I've played some games for an extra 10+ hours after I've finished playing the game just to tick off a couple of troublesome things. But when I 100% a game, I feel that I'm completely done with it and can put it away. When there's some left, unless I've given them a good shot I'll feel there's still something I could do with the game, but if I don't enjoy it, I may not come back to it. But it'll still sit in that folder of 'achievements incomplete' until forever.

I also note that I've got 3 of the games on the top 10 listed. but as a PC player, and early purchase, I have no idea on the Minecraft achievements, I've not played Saints Row and only have about 90 mins in Skyrim.