Work in the NFL is almost always temporary anyway. There are some exceptions, of course. Bill Belichick has achieved deity-like status in New England, even though the Patriots haven't won a Super Bowl since 2004 and there's a sense the head coach's magic has gone poof. Tom Coughlin, himself a hot-seat occupier in 2006, is now the king of the crusty old smart guys of football. Washington's Mike Shanahan, Chicago's Lovie Smith, Baltimore's John Harbaugh and Green Bay's Mike McCarthy are among the select few veterans whose positions are safe no matter how their 2012 seasons turn out.
But when it comes to coaches who have overstayed their welcomes by underachieving, you have to start with Norv Turner.
The San Diego Chargers (3-3) play the most boring, nondescript brand of football on the planet. Their logo is a lightning bolt, which suggests electricity. But it probably should be a different phenomenon of physics, like a vacuum. And that's because of Norv.
This is Turner's sixth season as the Chargers' head coach. His team last won a playoff game in 2008, a wild card triumph over the Colts. San Diego missed the playoffs the past two seasons. His star quarterback, Philip Rivers, is getting worse by the game. And the ultimate embarrassment came Monday night, when the Chargers lost 35-24 after leading 24-0 at halftime.
The Spanos family will likely clean house after the season, and Norv will be the first to get broomed out.
Andy Reid might be next. The difference between Turner and Reid is that the latter is perceived as an excellent coach, and will probably get another head coaching job a few minutes after he is let go by the Philadelphia Eagles. But he chose Michael Vick to be his starting quarterback, and Vick likes to give the ball to the other team. That's a problem.
The Eagles are currently 3-3, so it's conceivable they could start playing up to their potential. It's also possible Vick may learn to take care of the football. Yet turnovers aren't Vick's only problem: He's small and fragile, and if he doesn't cough up the ball, he might cough up a rib. That would leave rookie Nick Foles as the Eagles' starter, and as promising as he is, he's not ready.
In Dallas, Jason Garrett might be another casualty of the burning chair. He is currently under fire for his poor clock management at the end of his team's setback Sunday against Baltimore. He heard similar criticism last season. Right now there's a sense in and around the Cowboys that Garrett is learning on the job, that when he screws up and lets a victory slip away it's chalked up as a teachable moment.
But Jerry Jones is not the kindly headmaster of a boys prep school. He's a businessman who spent $1.2 billion to build a stadium. He wants results, and he wants them yesterday. Or the day before. He didn't seem to particularly like having Bill Parcells as coach because he couldn't work him like a marionette. Now he has the opposite problem, only the strings keep getting tangled.
Garrett likely will last out the year. And there's a chance the Cowboys, who are currently 2-3, could get on a roll, starting with Sunday's game at Carolina, which might give him some Norv Turner-like immunity for another season. Yet all that is unlikely. They have a fairly tough schedule, and there doesn't seem to be any factors ahead - like Dez Bryant suddenly becoming one of the good hands people - that work in Garrett's favor.
And Pat Shurmur in Cleveland is an easy one. Whether it's fair to blame him for the team's struggles isn't the issue. The Browns have a new owner in Jimmy Haslam. He just replaced Mike Holmgren with new CEO Joe Banner, who will want his own man as head coach. Shurmur will probably make it to the end of the season, and then he'll be asked to clean out his desk.
Those are the gentlemen whose backsides are being broiled. But turn down the heat a notch and there are others who are still feeling it.
The Detroit Lions showed a pulse last week by beating the Eagles in OT to improve to 2-3. But before that they had played lackluster football and had lost three straight. Jim Schwartz just got a contract extension over the summer, so he's probably safe for the most part. Still, considering the expectations the Lions faced coming into 2012, it would be natural if he felt a little squirmy if Detroit fails to make the playoffs.
All four teams in the AFC East are 3-3. The Buffalo Bills and New York Jets both have mediocre quarterbacks, which doesn't bode well for their postseason chances. In each case, the Bills' Chan Gailey and the Jets' Rex Ryan might have some explaining to do, although Ryan talks a better game and therefore is less likely to be canned than Gailey.
Then there is Mike Smith and the Atlanta Falcons. It may seem strange to put him on any hot seat when his club is 6-0. Yet regular season success hasn't been the problem with the Falcons. They haven't won a playoff game since Smith took over for the 2008 season. Last year was especially embarrassing, as Atlanta was bounced, 24-2, in an NFC wild-card game by the Giants. If the Falcons post a terrific regular-season record and then flop again in the postseason, owner Arthur Blank just might want to make a change.
In the NFL, job numbers are easy to sort out. They come down to wins and losses.
Michael Ventre is a regular contributor to NBCSports.com. Follow him on Twitter @MichaelVentre44