Jason Kenny, Great Britain's most successful Olympian of all time, has retired to take up a coaching job with British Cycling.
The 33-year-old won seven gold medals and two silvers between 2008 and 2021.
"A massive part of me would love to continue and try to get to Paris and I'm a little bit sad in a way to not do that," he told BBC Breakfast.
"The opportunity at British Cycling to be a coach might not be there in three years. I thought I'd take it now."
Kenny, who was knighted in the New Year Honours list, won team sprint gold in Beijing 2008, London 2012 and Rio 2016, individual sprint in 2012 and 2016 and the keirin in 2016 and Tokyo 2020.
"That keirin in Tokyo was special to me," he said. "It was an amazing race. If you could pick one to end on, that would always be. That did play a small part in it. That will be my last ever race, to finish on something so special on the last day of the Olympics."
That win made him the most successful cyclist in Olympic history from any country. He also won silver in sprint in 2008 and team sprint last year.
His wife, Laura Kenny, 29, who was also made a Dame in the New Year Honours, is the joint most decorated female athlete for Team GB, with five golds and one silver medal.
Why has he made the decision now?
Jason Kenny was 20 when he went to his first Olympic Games in 2008Kenny had previously said he was "not very optimistic" of being at Paris 2024 because of injuries.
"It's a combination of things," he told the BBC. "The opportunity came up at British Cycling to be a coach and it's something I wanted to do when I stopped anyway and it might not be there in three years so I thought for the sake of three years, I don't know if I can do three more years anyway, I thought I'd take the opportunity now.
"I'm really sad. It's all I've ever known is racing and training. I'm sad on that front but excited to start this new journey.
"It's a step into the unknown. I've worked with amazing coaches and I'm trying to unlock my memories of what I remember as a rider and what I liked."
British Cycling 'at a crossroads'
British Cycling - one of the country's best-funded and most successful sports - was also one of several sporting organisations criticised by a 2017 review for its culture in pursuit of success, including Olympic medals.
Ex-riders spoke of "a culture of fear", there was an apology over bullying and doping claims, and a 39-point action plan was introduced to improve athlete welfare.
And last year, former British Cycling and Team Sky chief doctor Richard Freedman was found guilty by a medical tribunal of ordering a banned substance to help an unnamed rider to cheat.
Asked about British Cycling now, Kenny replied: "I'd say it's at a crossroads. If we take the right road we can be successful, a good organisation moving forward.
"Hopefully a sustainable organisation. We've had turbulence in the last few years, restructure, new staff coming in. It's important we look after performance but do it in the right way. The next few years are really important.
"Being an athlete is really hard. There's a misconception they're treated like gods and paid millions. For the most part, being an athlete is really unpleasant. We want to make it as positive as possible. They're happy to go through it because everyone has that dream of winning. We have to be behind them, supporting them as best we can.
"That's where British Cycling needs to be on the high-performance side. That's the key - where we position ourselves. It's important we produce as many happy champions as we can. Everyone is here because they love the sport. We want to nurture that. We don't want people walking away hating cycling which has happened in the past."
Kenny says he aims to be a "positive" coach, adding: "When I look back at the coaches who got the best out of me, they were positive. It's contagious when someone is positive. You can't bash someone into being the best in the world or get the best out of themselves."
How does he reflect on his career?
Jason Kenny took at least one Olympic gold medal at every Games he went to"I just did my best and loved the process of getting to that point where you can have that special moment every four years," said Kenny. "That's always been my passion.
"Even now, I'm diving straight into this next role and trying to help support the lads, most of whom are at the start of their journeys. Hopefully I can help give them as good an experience as I've had."
Kenny overtook his friend Chris Hoy's British record Olympic haul of seven medals in total - and six golds - last year.
On which of his medals stuck out, he said: "The last one was very special because I know it's the last one now. But the team ones are always the most fun because you get to enjoy it with your mates."
Jason Kenny is the most successful British Olympian, while Laura Kenny is Britain's most successful female OlympianHow will family life change?
"When you're riding, you have a lot of free time," he said. "You can only train so much, but you can't use it for anything. It's recovery.
"I'll be hopefully less tired all the time.
"I can have a pasty for lunch because later while I'm working I'm not going on the track and won't throw it up. I can go and do gardening without thinking I'll be knackered at training."
Kenny is still cycling for fun. "I always struggled going out for a loop on my bike, it felt so pointless," he said.
Jason and Laura Kenny are Britain's most successful male and female OlympiansKenny said it helped his career being married to another elite Olympic athlete.
"That's going to change now Laura's carrying on and I'm stopping," he said. "That's going to be a new dynamic in our house.
"Living with a competing athlete is always challenging but it's also been good that we've been able to go through it together, grow together and go to the races together and spend all that really special time that's normally away from your family.
"It's been really special, we've been really lucky."
Between them, Jason (nine) and Laura Kenny (six) have won 15 Olympic medals