Michael Beasley has enormous potential and talent. He was traded so that the Miami Heat could afford to finalize the rest of the roster after signing LeBron James, D'Wayne Wade, and Chris Bosh. It wasn't that they were unhappy with him and wanted him out. While he has not quite lived up to his star-studded expectations yet, the 3rd year player will have a chance to prove himself this season in Minnesota.
The Minnesota Timberwolves traded a 2nd round pick for Michael Beasley, which most analysts have claimed it as a good steal for us (and it sounds like a first round pick swap sometime in the next 7 seasons, but it really shouldn't be that bad if you have 1 winning season in the next 7).