In most of the
trackers when your user rank goes up, like from user to power user > Elite user > Extreme user... egc, you get some extra benifit, extra features. It's like ranking up in games. And the only way to do that is by gaining lots of upload, bonus point, average seedtime,
ratio & seeding size size sometimes etc. Different
tracker applies different rules of their own.
On avistaz for example, you cannot download torrent which is uploaderd within last 7 days, when you'rea not in member rank.