New York Yankees pitcher Mariano Rivera announced this will be his last season - a full eight months before said retirement would begin. Why do athletes do this? Tony Gonzalez did it last year and now he regrets it because he wants to play again. Randy Moss retired then un-retired. Brett Favre. Michael Jordan. It worked out for Ray Lewis, but so many guys regret announcing their retirement. I much prefer the guys who just sit out a season, see how it feels, then retire.