- Where do the numbers come from?
- From the Steam libraries read on this site. For each game, the libraries that own it are counted, and the share is how many of them have never launched it, with zero minutes played. A game is only a card once at least 30 libraries here own it. They are libraries read here, not every Steam player.
- Why are free games left out?
- Steam only lists a free game in a library once it has been played, so every owner of one has launched it and the answer would always be zero.
- Why do so many owners never launch some games?
- Mostly bundles, sales and giveaways: a game that came free in a promotion, or as one of ten in a bundle, sits in many libraries that never opened it. Games people buy on purpose, especially ones played with friends, are almost always launched.