Long answer: Mitigating circumstances could force his hand, such as doctors telling him his neck is unstable and he's putting himself at extreme risk if he continues. Or if he decides he'd like to become a personal quarterback coach to help Eli cut down on those interceptions.
Medium answer: As long as Manning feels he can play at a high level, and the records and challenges exist, he'll stick around.
I can't imagine Manning walking off into the sunset now. Not after his greatest statistical season ever. Not after proving everyone wrong who doubted he could return to form again, and yes that includes the Indianapolis Colts tweet-loving owner.
Manning values the history of the NFL as much as any player. That was evident from the time he wanted to wear the black high-top shoes in honor of Johnny Unitas and the NFL vetoed the plan. Manning grew up seeing the game through the prism of his quarterback father, Archie. He was around the game as a child, he met NFL royalty, and he knows the history.
I would never say Manning values statistical achievements over winning. Quite the opposite. He's one of the most driven competitors of all time, someone who takes losing personally and has trouble shaking losses.
But that competitiveness also spills over into the personal records category.
Manning takes satisfaction in records, as he should. There's a reason why he kept throwing in big wins this year en route to 55 touchdowns and reclaiming of his single-season record broken by nemesis Tom Brady.
Manning remains within striking distance of three significant records, all held by Brett Favre (Packers, Jets, Vikings, Wranglers).
Favre holds the mark for career passing yards (71,838), career completions (6,300) and career touchdown passes (508). Manning is second in all three categories.
If Manning plays in 2014, he'll break the touchdown record. He has 491, only 17 behind Favre.
The other records would require two more years. He's 768 completions and 6,874 yards behind Favre's marks in those categories. In his last three full seasons (2010 with the Colts and the last two seasons in Denver), Manning has completed 450, 400 and 450 passes. That's a nod to the change in passing games. Prior to those years, he'd never cracked 400.
Manning has also had his highest yardage the last three full seasons: 4,700 with the Colts in 2010; 4,659 last season; and an NFL-record 5,477 this season.
So there's no way to catch Favre in one season in those categories. If you look at it strictly through the lens of records, Manning would need to commit to two more seasons to reach those marks.
Incidentally, Manning is tied with Dan Marino for most game-winning drives (51).
And, the good news: Manning will never catch Favre's 336 career interceptions. Manning has 219, barely in the Top 20 picks list.
The story after the season was that Manning will be checked by physicians sometimes after the Super Bowl against Seattle on Feb. 2 before being cleared to continue playing. This was touted as a breaking news story at the time, but that's debatable. Regular physical checks were part of his contract when he signed with the Broncos after being released by the Colts.
I'm no doctor, but he looks healthy, doesn't he?
Barring the remote possibility that Manning could be told he's putting himself at physical risk to continue playing, what other motivation would exist for retiring now?
He'll be 38 next season, which is getting up there, but Favre played until he was 41 and he took a more significant beating with his style of play. Favre was sacked 525 times in his career, the most in history. Manning has been sacked 270 times, which coincidentally ties him with Marino for 48th all-time.
Sacks don't take into account the hits a quarterback takes, but Favre, John Elway (second all-time with 516 sacks) and even Archie Manning (11th with 396) surely were rocked more times than Peyton Manning.
One of Manning's strengths is his ability to get rid of the ball before a hit and to go down with a limited contact sack if necessary.
It should also be taken into consideration that Manning sat out the entire 2011 season. Yes, it involved surgeries on his neck, but it also allow the rest of his body to take a year off from the grind and contact.
Does it make any real difference whether Manning ends up as the all-time leader or second in some of these categories? No, it doesn't affect his status for his induction into the Hall of Fame or to have his name in every debate about greatest quarterbacks of all time.
But being No.1 in completions, yards and touchdowns would be the icing, no?
The Manning retirement question won't ride on whether the Broncos beat the Seahawks and earn Manning a second Super Bowl ring. It won't ride on statistical standing, although there's no question Manning knows where he stands in all those categories.
It will ride on Manning asking himself if he thinks he can still play at the level he expects to play.
If that answer is yes, and there's no reason to believe it won't be, then we'll be watching Manning barking “Omaha!” and chasing Favre's records again next fall.