Michael Phelps has nothing to prove to anyone, but neither did Michael Jordan, Kelly Slater, or Gordie Howe. Still, these legends all got up off their laurels, un-retired, and tried to compete at a high level. Some succeeded. Others, not so much.
Why he hung it up: Phelps won 22 medals – 18 gold – across three Olympics, cementing his status (potentially permanently) as the most decorated Olympian in history.
Why he returned: So far, Phelps has been quiet on the subject, but we can only imagine he got tired of golfing and playing poker.
His Success: We're a long way from Rio 2016, but don't bet against Phelps. He's basically a sea mammal.
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