Retirement?

So how many times are these sports superstars going to retire. Call me crazy but I was under the impression that when you retired it meant you stopped playing your sport. Yet we see stars like Michael Jordan, Brett Favre, and Floyd Mayweather Jr. making returns to playing the games that they once played. I just don't get it. Make up your mind guys!!! If you feel the need to come back then you are obviously retiring for the wrong reasons. You are supposed to retire because you feel there is nothing more you can bring to the game, or for injury reasons, not because you want the publicity! So I'm here to tell all you superstar athletes out there...if you are going to retire, STAY RETIRED!!!