Unfinished = anything I’ve started and not done with yet
Beaten = there is some bonus content or achievements left, but I’ve comprehensively experienced the game
Completed = finished the game’s content and got all the achievements I wanted
Won’t play = either didn’t want the game in my library in the first place (from the early Humble Bundle days), changed my mind about playing it, or dropped it because I found it annoying / boring / broken.