16. DeMarcus Cousins
When he's on top of his game, the Kings forward/center is one of the best big men in the NBA. He's physically imposing. He knows how to bang on the boards and finish at the rim. And above all else, he's got tons of talent and still hasn't fully reached his potential. The trouble, of course, is that too often Cousins does really dumb things both on and off the court that overshadow his game. For instance, back in December 2012, he got suspended for "unprofessional behavior and conduct detrimental to the team" after he got into a heated argument with then-Kings coach Keith Smart at halftime of a game.
He also got suspended by the league one month earlier for confronting Spurs announcer Sean Elliott in what the NBA determined to be a "hostile manner." And last season, he was ejected from four of the 75 games that he played in for Sacramento. If he could just learn to channel his energy on the court and turn the negatives into positives, he would routinely be mentioned amongst the NBA's best big men. But instead, he continues to sabotage himself with his bizarre behavior.