Private trackers typically require users to seed torrents (upload) for specific times or to hit specific ratios (upload/download). Each tracker will have its own rules governing how much you can download (for example only downloading 1 Gb for each Gb uploaded, in a 1:1 ratio). Some trackers will use a bonus point system to incentivize long seed times or designate specific torrents 'freeleech' to not count towards your downloaded quantities. Users that have low ratio or upload may have limits imposed on their accounts, and users with high ratio/upload may get extra benefits. These schemes can be referred to as the tracker's economy.

The reason for the economy is to encourage users to seed torrents, to increase download speeds, and to lengthen the retention of older torrents' availability. Some trackers, typically more exclusive ones and public ones, are 'ratio less' and do not track these statistics and limits.