Why did Keith Olbermann leave MSNBC?

(Post updated at 4:54 PM ET)

Keith Olbermann's abrupt departure from MSNBC shook the media world Friday and left plenty of questions behind about whether the MSNBC star jumped or was pushed. Olberman, often bombastic and dripping with outrage, left the studio by offering thanks but no real explanation.

MSNBC issued a brief statement during Olbermann's sign-off, noting only that the two sides "ended their contract" and that the network wished him "well in his future endeavors." And with that, after eight years, MSNBC's top-rated and most outspoken host -- the anchor behind which the cable news network repositioned itself as a liberal alternative to Fox News in the evening -- headed for the exit at 30 Rock.

While Olbermann and MSNBC aren't talking about what specifically led to the departure, the host's move doesn't come as a big surprise given their recent history.

Olbermann has clashed with his bosses throughout his career, had recently been suspended and reportedly threatened with firing by MSNBC, and MSNBC's parent company NBC Universal recently merged with the cable company Comcast. All three could have played a role.

Olbermann suggested that the timing of his departure may have been out of his control.

He joked, referencing the famed "mad as hell" scene from the movie "Network," about fantasizing about ranting against management after being "told that this is going to be the last edition" of his show. But Olbermann remained comparatively calm in making Friday's announcement:

It doesn't seem even those close to Olbermann knew much of the decision to finally leave. MSNBC's Rachel Maddow was asked about the sudden move Friday on HBO's "Real Time with Bill Maher." Maddow said she didn't know much of the details but simply stated that "he and the company made a mutual decision that 'Countdown' is done." Maher didn't buy that explanation. "That's always bulls--t," he said.

Olbermann hasn't yet offered a full explanation and he's been uncharacteristically quiet on Twitter. So while it's not clear what the final straw was, there have been indications in recent years that Olberman and MSNBC would eventually go their separate ways.

Clashes with NBC/ MSNBC brass: It's never easy to manage someone who doesn't seem to care if they get fired. Olbermann already left MSNBC once before, in 1998, and stormed out of other networks before. One former ESPN colleague told the New Yorker that when Olbermann left the sports network in 1997, "he didn't burn bridges here—he napalmed them." And Olbermann was never shy about asserting that he—and not MSNBC Phil Griffin—called the shots on his 8 p.m. show. "Phil thinks he's my boss," Olbermann said in the same 2008 New Yorker profile.

Fallout from the suspension: MSNBC cracked down on Olbermann in November after it was revealed that he gave donations to three Democratic candidates running in 2010, including Arizona Rep. Gabrielle Giffords. Of course, Olbermann's political views are well known. But MSNBC said that Olbermann needed to ask permission first before making political contributions and, therefore, violated network policy. Olbermann ended up only being sidelined for just a couple days. But during that time, The Daily Beast reported that Griffin threatened to fire Olbermann is he accepted interview requests to tell his side of the story on another network.

Comcast's arrival: MSNBC is pushing back against the inevitable speculation that Olbermann's departure is related to Comcast taking the reins (and perhaps wanting to start things off without the combative host). Comcast, in a statement, said that the NBC deal hasn't closed and the company still "has no operational control at any of its properties including MSNBC" along with no plans to "interfere with NBC Universal's news operations." Olbermann wasn't worried about Comcast back in August 2010, telling New York magazine that the merger "augurs well for all of us here." It would be interesting to know what he thinks now.

NBC/ MSNBC tension: For years, some NBC executives and stars have questioned whether Olbermann's strident views tarnish the NBC News brand. Veterans like Tom Brokaw and Andrea Mitchell have privately expressed concerns about Olbermann's partisan views, while MSNBC's coverage of major news events—such as the 2008 convention and 2010 midterms—raised questions about having opinionated hosts like Olbermann in the anchor chair. In October, the New York Times reported that top executives were even considering changing the name of MSNBC.com—the network's highly trafficked, non-partisan news site—because of a perceived connection to the cable network's liberal talkers.

MSNBC's deeper bench: Fox News's Bill O'Reilly continues to attracted the biggest audience at 8 p.m. (and across cable news). But Olbermann still brought in much stronger ratings to MSNBC than in the past and the network surpassed CNN for second place in primetime last year. Since Olbermann showed there was a market for left-leaning opinion in primetime, MSNBC has given hourly shows to three more liberal commentators over the past few years: Maddow (2008), Ed Schultz (2009), and Lawrence O'Donnell (2010). As a result, there's a perception that MSNBC may no longer need Olbermann as much as it did when he was the lone, liberal star. Shortly after Olbermann broke the news on-air, MSNBC sent out a press release promoting its new line-up, with O'Donnell at 8 p.m., Schultz at 10 p.m., and Cenk Uygur—an MSNBC contributor and host of the liberal web show, "The Young Turks"—filling in at 6 p.m. There was no mention of Olbermann in the release.

It's unclear where Olbermann goes from here. CNN has courted him in the past and clearly needs help at 8 p.m., with "Parker Spitzer" still not finding its footing (or much of an audience). Since Olbermann's bashed Fox News so relentlessly over the years, it's doubtful that even Fox News chief Roger Ailes—renowned for going against the grain—would try hiring him.Still, Olbermann may be off the air for an extended period of time as part of his settlement with the network, according to the New York Times. Perhaps Olbermann could return to sportscasting or simply leave cable television behind. The Wrap hears that he has ambitions to start his own "media empire," a la The Huffington Post.

Olbermann, who's been mad as hell on many occasions, whether railing against the Iraq War or the Bush administration's response to Hurricane Katrina, wrapped up his second stint on MSNBC with a James Thurber story of a Scottish terrier whose first instinct is to fight before knowing the full story. Before signing off, Olbermann provided the moral of the story: "It is better to ask some of the questions," he said, "than to know all of the answers."

UPDATE: While the direct cause of Olbermann's exit from MSNBC remains unknown, according to the New York Times the two parties had been negotiating the terms of a separation for weeks. The final terms both prohibit Olbermann from discussing the deal publicly and limit his ability to work on television in the near future.

(Oct. 2010 screen grab of Olbermann: AP /MSNBC)