14. Shaquille O'Neal to the Suns
Trade: Miami Heat get Marcus Banks and Shawn Marion; Phoenix Suns get Shaquille O'Neal.
Shaq was already way over the hill by the time Phoenix acquired him for All-Star Shawn Marion and salary cap fill-in Marcus Banks. Acquiring Shaq was essentially the death knell of the Mike D'Antoni "seven seconds or less" era Phoenix Suns. Shaq's style of play conflicted with the rest of the Phoenix roster and their record suffered. The only full season Shaq was with Phoenix they missed the playoffs (with 46 wins in a loaded conference), and as soon as they traded the Diesel, they made it to the Western Conference Finals the next year. That's what we call an "if it ain't broke don't fix it" trade.