@Jay: There are a few reasons for that.
- The stats only started counting a little while before the steam release.
- They don't take into account any challenges a player did before they started counting up.
and also, the stats are uploaded at the time of the action, not stored and uploaded later, so there's a fair chance many stats didn't get through based on stuff like having no internet connection at the time, or the db reaching it's connection limit at the time of upload. We are going t look at solving these problems in the near future.