Quality of play/teams that have frequent turnover, not good for fans who have historically grown to be attached to players in their team over the course of their career, probably not good for player legacies if they just bolt year after a good season to go to the highest bidder.
One of the great things about sports to me was the team, the commradery and the shared experience of working, grinding and building something - that may be lost for a lot of guys if they just jump from program to program.