Not every coach is appreciated in his time. Just ask Jim Harbaugh.

Before returning to Ann Arbor to save his alma mater, Michigan's leading man was ran out of San Francisco by GM Trent Baalke. Even his own players reached their boiling point.

Jim Harbaugh Not Denying Andrew Luck Reunion

"He does a great job of giving you that spark, that initial boom," 49ers guard Alex Boone told Andrea Kramer on HBO's "Real Sports With Bryant Gumbel," per ProFootballTalk. "But after a while, you just want to kick his ass. He just keeps pushing you, and you're like, 'Dude, we got over the mountain. Stop. Let go.'

"He kind of wore out his welcome."

Jim Harbaugh Blamed The Wrong People For Michigan State Loss

Harbaugh's not alone in that regard. Below are the most polarizing coaches in all of sports.

Bobby Petrino

Petrino didn't exactly wear out his welcome with the Falcons. He just quit, literally.

Leading the Falcons to the bottom of the NFC South with a 3-10 record in 2007, Petrino left notes at the locker of each player when he resigned before Week 15.

Jose Mourinho

No one wears out their welcome better than Jose Mourinho.

Chelsea had enough in 2007. Real Madrid had enough in 2013. Chelsea -- for whatever reason -- thought they made a mistake, rehired Mourinho in 2013 and "mutually parted ways" again on Thursday.

Nick Saban

As much as Nick Saban is a football God in Alabama, he's a pariah in Miami.

Despite proclaiming he wouldn't be the next Alabama head coach in Dec. 2006, Saban was officially introduced in Tuscaloosa on Jan. 4, 2007.

Rex Ryan

Loud, boisterous and .500 at best, that's Rex Ryan in a nutshell.

After leading the Jets to consecutive AFC Championship appearances, Ryan's antics and Super Bowl guarantees wore thin next to a 4-12 record. He was fired by the Jets on Dec. 29, 2014 and given a second chance by the Bills on Jan. 12, 2015.

For more content, follow us on Twitter @SportsWN or LIKE US on Facebook.