Team makeup and drafts are different. In leagues with a fairly static line-up of teams and relative ease for players moving between teams season-to-season, they

Team makeup and drafts are different. In leagues with a fairly static line-up of teams and relative ease for players moving between teams season-to-season, they're designed to prevent the league from rapidly sorting into permanent winners and permanent losers (like, the kind that gets shut out and embarrassed by mid-tier teams routinely, not that just loses more than half the time), the latter of which will tend to wither and die. It's basically a risk reduction scheme for all parties spending money on the teams (the owners; cities that build stadiums).