It's difficult for a professional athlete to decide when to retire.
It's painful for us, the fans, to watch our heroes stick around for too long and lose time and time again in devastating fashion.
However, it's hard for an athlete to just walk away from a sport that their life has revolved around for many years.
For those competitors who achieve greatness in their respective sports, it's even more difficult to let it go. Imagine going from being one of the best in the world at something, to completely irrelevant.
Sounds like a tough blow to swallow, no?
In mixed martial arts, we have seen many a fighter stick around for too long and it's always a sad sort of affair.
You see them being interviewed about their next fight and they always talk about how they're finally back in shape and ready to make a run towards the title again.
In your heart, you hope that they can pull it off, but in your head, you know they almost definitely won't.
While I do think that fighters should retire once they clearly have nothing left to give the sport, there's something deeply respectable about a guy who doesn't want to let go of his dream.
Let's take a look at the 20 worst fighter declines in the history of mixed martial arts...
These are fighters who are definitely on the decline, but still doing not too bad. They're still having some success, but they should think about retiring soon.
Matt Hughes: One of the best ever. Hughes is a two-time welterweight champion and holds the record for the most wins in the UFC, with 18. Matt lost the welterweight title five years ago and has amassed a decent record of 4-3 since then, but hasn't looked nearly as dominant as he used to.
Antonio Rogerio Nogueira: Nogueira is a legend of Pride. During his time with that promotion, he faced some of the top fighters in the world and was successful much of the time. Since entering the UFC back in 2009, Antonio hasn't looked the same as he did in Pride. His first fight with Luiz Cane was impressive, but his last three bouts have been lackluster.
Mike Brown: A former WEC featherweight champion. Brown won the title in 2008 and defended it twice against Urijah Faber and Leonard Garcia. Mike lost the belt to Jose Aldo and hasn't really looked the same since. He's 1-3 in his last four fights and, at 35 years old, it might be time to hang 'em up.
Keith Jardine's career has taken a really harsh turn these past few years.
He beat Chuck Liddell back in 2007 and fans started to believe that Keith might have a legitimate chance of becoming champion.
Jardine dropped his next fight to Wanderlei Silva, losing by first-round KO, but bounced back with a win over Brandon Vera.
After that, he lost four straight in the UFC and was released by the promotion.
Keith then lost his first fight after being canned by the UFC. It was a split decision loss to Trevor Prangley, who has never been a UFC-quality fighter.
From there, Jardine went on to win two fights against complete nobodies and fought to a draw with Gegard Mousasi. The fight would have been a win for Gegard, but he was deducted a point for an illegal up-kick.
Keith would be further up this list, but in order to decline, you first have to rise and Jardine was never really a dominant force.
Like Keith Jardine, Marvin Eastman would be further up this list, but he was never really an elite fighter, so he didn't have as far to fall as others you'll see in the coming slides.
However, at one point in his career, Eastman was a pretty solid fighter. He could never hang with the best, but he was a good gatekeeper.
Marvin even owns a victory over Quinton Jackson from way back in 2000.
In his last eight fights, Eastman has gone 2-6 and his only two victories are against competition so irrelevant to the sport that it's not worth my time to write out their names.
Many of you are probably surprised to see that Antonio Rodrigo Nogueira isn't further up the list.
When I started this piece, I thought he would be higher up too, but go look at the guy's record.
He's 3-2 in the UFC since entering the promotion in 2007 and his only losses have come to top competition.
Just because the guy can't take a punch like he used to, doesn't mean that he is completely irrelevant to the sport all of the sudden.
B.J. Penn suffered back-to-back losses to Matt Hughes and Georges St-Pierre and then went on to have the most dominant lightweight championship reign in UFC history.
You see what I'm saying?
Nogueira is certainly past his prime, but he has a lot more fight left in him than people think.
We'll see just how much fight when he takes on Brendan Schaub at UFC 134.
Same story as Rodrigo Nogueira; Fedor's decline has been blown out of proportion by many.
He was one of the most dominant figures in the sport for years and years and is considered by most to be the greatest heavyweight fighter of all-time.
Then he loses two fights and suddenly he's washed up.
I'm not saying that Emelianenko isn't declining, I'm saying it's two fights.
Not to mention that those two fights were against two heavyweight fighters who are considered to be among the top 10 in the world.
There's so many guys on this list who have stuck around and started losing to absolute nobodies that I can't have Nogueira and Fedor too far up, just because they're losing to the best in the world.
Sean Salmon has never been an elite fighter. In fact, he is most famous for getting kicked in the face by Rashad Evans.
That said, Salmon had himself a pretty respectable MMA career at one point.
In 2007, Sean had a record of 14-4.
Today, he has a record of 18-15.
Salmon is 4-11 in his last 15 fights and is currently on a six-fight losing streak.
Joe Stevenson is the winner of the Ultimate Fighter Season 2 and one of the most promising prospects in the history of the UFC's lightweight division.
In fact, the UFC had such faith in him that when they needed someone to fight MMA legend B.J. Penn for the vacant lightweight championship at UFC 80, they gave Joe the nod.
Stevenson was absolutely dismantled by Penn and never looked the same again.
Although he didn't look as dominant as he did before fighting B.J., Joe did have some success after his devastating loss.
He went 3-2 in his next five fights and beat some respectable competition.
Unfortunately, Stevenson lost to George Sotiropoulos at UFC 110 and it's been all downhill from their. Joe lost his next three fights, his last loss coming in the featherweight division, which he dropped to out of desperation after losing three straight at lightweight.
Brandon Vera started his mixed martial arts career with an eight-fight unbeaten streak, the eighth being a TKO over former UFC heavyweight champion Frank Mir.
Almost immediately after entering the UFC, Vera called out then light heavyweight champion Chuck Liddell and claimed that he would be the first UFC fighter to hold titles in two weight classes, simultaneously.
Things didn't exactly work out the way Vera planned...
After beating Mir, Vera lost his next two fights to Tim Sylvia and Fabricio Werdum.
As a result of those humbling defeats, Brandon moved to the light heavyweight division, hoping to have more success there.
While Vera did enjoy some success in his new weight class, he was only able to defeat B level fighters and lost consistently to top competition.
It's hard to believe that five years ago people actually believed that Brandon might make good on his prediction that he would hold two UFC belts at the same time and it is now painfully obvious that will never wear UFC gold.
A month ago, Tito Ortiz would have been much higher up on this list.
Ortiz is one of the greatest champions in the history of the UFC's light heavyweight division, which is historically the promotion's most stacked division.
Tito won the title in 2000 and defended it five times, which is a UFC record to this day.
After losing the belt, Ortiz put together an impressive string of wins to earn himself another crack at the strap.
His second chance at the light heavyweight belt was a rematch with Chuck Liddell, who had already beaten Tito.
Chuck would beat Ortiz again, via third round TKO, and that was the start of some rough times for Tito.
That loss to Liddell was the start of a five-year stretch that Tito would go without winning any fights.
Earlier this month at UFC 132, Ortiz showed that he still has something left to prove in the UFC when he submitted Ryan Bader in the first round.
That win saved him from being among the top five in this list.
David Loiseau was one of the most feared competitors in the middleweight division, at one point in time.
Unfortunately, David had his will broken by Rich Franklin when they fought for the UFC middleweight belt at UFC 58 and didn't look the same after that.
Loiseau has been bouncing back and forth between the UFC and minor promotions since his loss to Franklin.
Davis can still win fights against nobodies in the little leagues, but he has lost every UFC fight he's had since fighting Rich.
The only reason the UFC keeps bringing this guy back is to fight on events held in Canada.
Let's be honest, Tank Abbott was never that good.
As a pure mixed martial artist, he's actually one of the worst ever, given that he hasn't evolved even a little bit in the past 16 years.
However, seemingly lifetimes ago, Tank was a significant fighter and a legitimate threat to top level fighters.
Then the sport evolved and Tank did not, but he kept competing anyways.
It's really hard to look at Abbott's record from 1998 and onward.
Tank went 2-8 in his last 10 professional fights. All of them ended in the first round.
Shonie Carter is one of the greatest journeyman fighters in MMA history and is most famous for his spinning back fist knockout over Matt Serra back at UFC 31.
Carter started out in 1997 and to this day has more than 80 professional fights.
It's been some time since Shonie was in his prime, but he was at least still winning fights for a while beyond it. He was beating mediocre competition, but winning is winning, I suppose.
Regrettably, Carter can't even keep up with no-name competition these days.
He's gone 1-8 in his last nine fights, with his only somewhat notable opponent being Carlos Newton.
Mark Coleman could maybe be a little higher on this list, but the fact his win-loss ratio towards the end of his career isn't that bad saves him a bit.
That said, the former and first UFC heavyweight champion looked absolutely awful in his last fight.
At UFC 109, Coleman fought fellow UFC Hall of Famer Randy Couture and was defeated by second round submission.
Mark looked like a husk of his former self.
He gassed almost immediately. It was like he wore himself out just walking out to the Octagon.
At this point in Couture's career, he had slowed down significantly and Coleman made Randy look fast.
Kevin Randleman is a former UFC heavyweight champion and, at one point, boasted a record of 14-5.
At that time, he had victories over respected fighters such as Renato Sobral, Pete Williams, Pedro Rizzo and Murilo Rua.
Today, Kevin's record is 17-16 and he is 2-9 in his last 11 fights.
Mirko Cro Cop is a legend in MMA and has the most feared kicks in the history of the sport.
He definitely needs to retire, but when you look at his win-loss record for the last couple years, it's not too shabby.
Cro Cop is 5-3-0-1 in his past nine fights.
However, he has lost his last two fights by devastating knockout and it's clear that he just can't take punches like he used to.
Now would be a good time for him to get out of the sport, before he tarnishes his legacy.
Andrei Arlovski's situation is similar to that of Mirko Cro Cop's; he just can't take a good punch anymore.
Arlovski is one of the best heavyweights to ever compete in the sport and a former UFC champion, but he's lost his last four fights and three of them by first-round knockout.
It's sad to say, but it's for him to move on.
Chuck Liddell is the greatest light heavyweight in UFC history and arguably the most iconic figure in all of mixed martial arts.
When Chuck met Quinton Jackson for the second time at UFC 71, he was thought to be unbeatable.
He had already defended his belt four times and people were expecting him to run through Quinton Jackson (casual fans didn't really know Quinton at this point).
However, Jackson ended up knocking Liddell out in the first round and that was the beginning of the end for Chuck.
The once great champion would go 1-4 in his next five fights after losing to Quinton and closed out his career by losing three straight fights by knockout.
Wanderlei Silva is finished in this sport and here's why: he's a brawler with no chin.
Brawling can be a very effective style, but in order to pull it off, you have to be able to take a good shot.
Silva's been in the sport since the mid 90's and has accomplished more than most fighters can even dream of.
He should take solace in the fact that he will always be remembered as one of the best ever and gracefully make his exit, before his record gets any worse.
As it sits, Wanderlei has lost six of his last eight and four of those losses have come by knockout.
Tim Sylvia is a two-time UFC heavyweight champion.
For years, he took on some of the best fighters the heavyweight division had to offer and did extremely well.
However, since leaving the UFC in 2008, Tim has looked like garbage.
He is 4-2 in his last six fights, but all of his wins have come against mediocre competition.
Tim has jumped into the super heavyweight and currently is probably in the worst shape he's ever been in.
In 2009, Sylvia embarrassed the whole sport of mixed martial arts by losing to a washed up boxer in an official MMA match.
Ken Shamrock fought professionally for the first time in 1993 and is still fighting today.
Any time a fighter sticks around for that long, it's not pretty, and Shamrock is no exception.
When the UFC first started, Ken was a superstar.
He did very well in the early tournaments and held the long forgotten about Superfight championship and defended it twice.
Since then, the sport has grown a lot more than Shamrock has.
He is 4-10 in his last 14 fights with most of his losses coming by stoppages, and his most recent losses coming to bus league competition.
Jens Pulver is the first ever UFC lightweight champion.
Early in his career, he defeated tough fighters such as B.J. Penn, Dennis Hallman and Joe Stevenson.
Pulver has lost nine of his last 12 fights with all but one of those losses being first round stoppages.
The man can't hang with the best in the world anymore. Hell, he can't even hang with mid-level fighters.
Jens is fighting guys who aren't even top 100 in their divisions right now and barely holding his own.