UFC fighters know that their days at the top are numbered and there will come a point when they realize their best years have passed them by. When that happens, it's suddenly time to hang up their gloves.The fight game takes an immense toll on the minds and bodies of fighters and their careers are often shortlived in comparison to athletes from other sports.The question UFC fighters often struggle with is when is the right time to retire? Due to the violent nature of the sport, fighters usually absorb a lot of damage over the years and after a point, call time on their professional careers to avoid risking permanent damage.While some fighters like Khabib Nurmagomedov and Georges St-Pierre are smart enough to walk out while still on top, there are others who end up over-stretching their careers.MMA mania@mmamaniaWatch Khabib's retirement speech #UFC254 2:45 AM · Oct 25, 202012935Watch Khabib's retirement speech #UFC254 https://t.co/FICTd4GCphThere are also fighters who've accomplished their goals in the promotion and have nothing more to look forward to, as well as those who can no longer achieve their goals. Some fighters even lose the motivation to undergo rigorous training to keep themselves in peak condition after amassing a lot of wealth.Heading into a new calendar year full of high octane UFC fights, let's take a look at five fighters who might pull down the curtains on their careers in 2022.#5. Jorge Masvidal - UFC welterweightJorge Masvidal already unsuccessfully challenged for the welterweight title twiceUFC welterweight contender Jorge Masvidal is one of the most popular fighters today. After resurrecting his career with a spectacular knockout victory against Darren Till, 'Gamebred' finally started getting the attention he always deserved.Masvidal's popularity shot through the roof when he knocked Ben Askren out cold with a flying knee in just five seconds, registering the fastest KO in UFC history. 'Gamebred' then famously stopped Nate Diaz via TKO (doctor's stoppage) in their 'BMF' title fight at UFC 244.Shafi Chowdhury@Shafi20305 second knockout 🤯 masvidal just knocked out ben askren8:51 AM · Jul 7, 20193121335 second knockout 🤯 masvidal just knocked out ben askren https://t.co/iPlMTi4ENoSince then, however, Masvidal's career has hit a downhill slide. The Miami native fought Kamaru Usman for the title on short notice at UFC 251, stepping in as a late replacement for Gilbert Burns.Usman completely stifled Masvidal's striking in the fight with his dominant wrestling. After five rounds, Usman was declared the winner via unanimous decision.UFC on BT Sport@btsportufc"Give me six weeks man."The words @GamebredFighter said to Dana White after UFC 251. Now Kamaru Usman has given him a full camp and another shot. How will it play out?(🎥 UFC Countdown)12:06 PM · Apr 20, 20217158717"Give me six weeks man."The words @GamebredFighter said to Dana White after UFC 251. Now Kamaru Usman has given him a full camp and another shot. How will it play out?(🎥 UFC Countdown) https://t.co/L8JhBxK2MVAt UFC 261, Usman gave Masvidal a second crack at the title, this time with a full fight camp behind him. While 'Gamebred' seemed confident heading into the rematch, he found out why Usman is nicknamed 'The Nigerian Nightmare.'In the second round, Usman knocked Masvidal out cold with a devastating right hand.Vover@voveraudioThis angle of Usman's KO of Masvidal 😤 #UFC261 [h/t IG/chasskelly]1:38 AM · Apr 26, 202118948This angle of Usman's KO of Masvidal 😤 #UFC261 [h/t IG/chasskelly] https://t.co/NfV3MBCF91With back-to-back title fight losses, it seems like Masvidal won't get another title shot as long as Usman remains champion. He could fight Colby Covington in a grudge match, something that would certainly intrigue fans, but even winning that fight wouldn't land him another title shot.Masvidal may even seek newer pastures inside the boxing ring, as Jake Paul has been calling him out of late. A big paycheck to take on 'The Problem Child' is an opportunity Masvidal would likely relish. To do that, however, he must first part ways with the UFC.At 37, Masvidal isn't getting any younger and already has 50 fights under his belt. He has made a lot of money from the sport and the knockout he suffered against Usman must've taken a lot out of his chin, which had already taken some punishment over the years.As far as MMA is concerned, it may be time for Masvidal to walk off into the sunset. He should probably take the money fight against Paul, grab that paycheck and then shift his focus to the various other ventures he has his hands in.