Asked to elaborate on the reasons for his decision, he denied the birth of his first child Alessandra in February had been a pivotal factor.
The dumbing down of rules to let tweaked 1000cc production engines to race in MotoGP was a factor, further removing the series away from its prototype ethos.
“I've been watching this championship a long time and it is very easy to see what works and what doesn't.
"This championship and everything I've done to get here has been a huge dream of mine and then to realise a lot of things, whether it's people having no faith in you or people not believing in your talent or the changes that have happened to the championship.
"2009 was a big eye-opener to me, everyone still until this day says it was a mystery illness, the fact that no one understands that I have a lactose intolerance, which is really critical, it just takes all my energy and stops me from absorbing nutrients. No one listened to me on that. Many things over time have taken their toll.
"The direction I see the championship heading and the fact that in 2009 I realised what was important and that's family and happiness. Money isn't everything. I think that I am one of the few riders who can actually say they have retired when they have stopped enjoying it.
"My passion has slowly ebbed away from this championship. It is not the championship I fell in love with. It is not the championship I always wanted to race in. This is a MotoGP championship, this is a prototype championship.
"People can talk about the past with it starting as standard machines and progressed to prototype machines, now we are taking the opposite step and going backwards.
"There are many, many different reasons, but it is basically me losing my passion for the racing and my enjoyment of this sport. For sure I will enjoy it this year but for sure if I continued it would only be a mistake on my behalf. It wouldn't be correct to Honda and my team if I didn't give 110%.
"I've loved bikes, this is my whole life and if I keep doing it I'm afraid I'm going to lose my passion and not want to go near a bike for the next 10 years, and that would scare me, "said Stoner.
