For a professional athlete, knowing the time to call it a day from their chosen sport can be one of the hardest things they have to do.
For those involved in boxing, the bright lights, glamour, and massive amounts of money on offer can be incredibly hard to walk away from.
While fans love to see their idols take to the ring, however, it can be a sad sight to see fighters well past their prime struggle in a sport they used to excel in.
Former heavyweight world champion David Haye made that tough decision on Tuesday, with the 37-year-old retiring after 32 fights with a overall record of 28 wins (26 by KO).
The writing was on the wall for Haye with a serious Achilles injury occurring during his fight to Tony Bellew in March 2017.
Those sorts of injuries are notoriously difficult to recover from, let alone for an aging boxer, but he bravely wanted to finish his career on his terms, as a rematch was arranged with Bellew.
However, when they met again last month, it was clear that Haye had lost a step and was unable to keep up with the younger Bellew, eventually losing in the fifth round.
It is always pleasing to see tributes paid to retiring athletes, especially from those who were in the same industry.
Retired middleweight fighter Carl Froch was glowing and heartfelt documenting the career of his friend in his own words.
Sky Sports reported Froch as saying: "I am glad David has retired, but I hope he won't be remembered for the two defeats against Tony Bellew, he has had one hell of a fantastic career.
"Yes, he had one or two too many losses late in his career, but David Haye is one of the best boxers Britain has produced.
"To be undisputed cruiserweight champion of the world was brilliant, but then he went on to become a heavyweight world champion.
"To do that, when he was nowhere near a heavyweight, especially against that giant Nikolay Valuev, deserves massive respect.
"Going to Paris to take on Jean Marc Mormeck in his own backyard, to take on Valuev, then Wladimir Klitschko and other guys so much bigger than him, showed how brave he was.
"David was a master at making the fight as entertaining as possible. Yes some people hoped he would have egg on his face, but people like me liked to watch him in the ring.
"Everyone knows what the Klitschko fight was like, the same with Audley Harrison, but even back then it was clear he was taking a massive risk, going in with proper heavyweights.
"As a friend of David's of around 20 years, I didn't want to see him make the recent comeback, but that is David. His career was fantastic to follow and watch, and it was a rollercoaster ride.
"David Haye's natural ability and class shone through and even if he hasn't finished on top, he is one of the best fighters this country has seen.
"He was explosive, he was entertaining, and he was always worth watching."
Nothing else needs to be said other than well done David on a fine career, and all the best for the next phase of your life.