Hart was first-choice for the Sky Blues before Guardiola's arrival at the club in 2016.
The former Barcelona boss moved quickly to secure the services of experienced Chilean Claudio Bravo from the Catalan giants in a £17million deal, with Willy Caballero then stepping up to provide cover as the No.2.
Guardiola made it clear he wanted a goalkeeper more capable with the ball at his feet.
Hart has revealed he had a two-hour conversation with the Catalan, trying to persuade Guardiola to give him the chance to impress - to no avail.
"I wanted to get in the door and have this conversation," the current Celtic goalkeeper told the 'In The Stiffs' Podcast.
"He was very knowledgeable on my background, very knowledgeable on what we did, how I played football, it was a two-hour conversation that kind of ended with him saying 'I can't see this working.'
"I said 'I don't agree with you.' He said. 'I'll be the first person to be proved wrong but what I see in you isn't what I want from my goalkeeper.'
"I was like, 'it's only fair I be given the opportunity.' He said, 'of course you'll be given the opportunity, but…' As soon as there are any 'buts' at the end you know there's a decision.
"I wanted the opportunity to be coached by one of the best at it. Of course I didn't know how to do it, why would I know how to do something that I'd never been asked to do or taught to do?
"I suppose he was right, I couldn't do it, he couldn't just drop me into a team to play like he wanted to at that moment in time.
"It was taken away from me, but so what? I'm not bigger than anyone and if that's my path then that's my path. The people of Manchester City will forever be in my heart, I'll forever be grateful for that, but the team, the hierarchy, they're businessmen."
During his time in Manchester, Hart made 347 appearances in all competitions before he eventually headed out on-loan to Torino.
After his short spell in Serie A, he returned to the Premier League joining West Ham in a temporary switch, before completing a permanent move to Burnley, while he also spent a season with Tottenham.
Now 34, Hart is looking to help Celtic to the Scottish Premiership title.
The Bhoys are currently three points ahead of arch-rivals Rangers in the race to become champions.