Should have retired: After his second retirement
After logging six NBA championships, the greatest of all time called it quits for the—and this time it's for real—second time. His inevitable return to the court with the Wizards two years later bore an inglorious pair of seasons, leaving the man wandering in his Hanes like any other retiree.
Should have retired: September 12, 2001
Of all the heroes of 9/11, the former mayor of New York was arguably the biggest. Come to think of it, he probably should have mentioned that during his run for president.
Should have retired: Following his third posthumous album
Still I Rise marked the third postmortem release of "new" material by hip-hop's most prolific decomposer, and the diminished quality of his remaining work was conspicuous in three subsequent efforts. We know there's a recession, but if 2Pac can't retire after being dead four years, the rest of us are screwed.
The Atlanta Falcons' 2008 First-Round Pick: Matt Ryan
Should have retired: On Draft day
Mike Vick didn't just put himself in lockdown for the next few years, he sentenced his team to pounding license plates for three to five as well. Following all this chaos, the Birds' new rookie sensation would be best served preemptively setting his signing bonus aside for bail.
Should have retired: After Police Academy 2
Police Academy and its subsequent sequel made him a comedy star. Police Academy 4, on the other hand, made him a comedy punch line. Guttenphiles may cry foul for not including the elderly-endearing Cocoon, but those people are mostly all dead by now.
Should have retired: Right after the Super Bowl
The impossible became history when Peyton Manning's younger brother (we're told it's Eli—Google returned no results) led the scrappy Giants to victory over the undefeated Patriots in Super Bowl XLII. Now's the time he finally lives up to expectations, steps out from his brother's shadow, and... Ooh, quiet! Peyton's priceless pep talk commercial is on!
Should have retired: When he beat Mike Tyson
From out of nowhere, the buffet bruiser floored an undefeated Iron Mike for the heavyweight title, and for one moment became the most feared man in the world (the crown now held by Oprah). But his reign was short lived, and without the championship belt, his gut is all that's holding up his Everlasts.