Jeremy Clarkson's firing from Top Gear and the departure of James May and Richard Hammond from the show were the pinnacle of "a perfect storm" that was building between the programme and the BBC, the executive producer has said.
Jeremy was sacked following a "fracas" with a producer over hot food in 2015, and his co-hosts left soon afterwards.
Andy Wilman, who served as executive producer on Top Gear and is now executive producer of the trio's new motoring show The Grand Tour for Amazon Prime, said the events in March last year were the culmination of a "broken relationship" that became "personal and confrontational".
In a frank conversation at the Edinburgh TV Festival, Andy said: "I think it was a perfect storm that was coming. That show got bigger and bigger by accident, we never adjusted to that and were collapsing under the weight of the work we were doing. We got to series 22.
"We had s**t like Argentina go wrong, so it was all building. I'm speaking as someone who loves the BBC and there were a lot of people who were great with us and some people there weren't great with us and didn't want us there so it became a battle.
"It became personal and confrontational and when everything went to s**t in March, that was critical because it was going to be a victory for somebody.
"It wasn't going to be a resolution because I think some people didn't have the will to make it work on the management side, and I didn't have the maturity to make it work either. Everyone had taken their position, we were all entrenched."
The Grand Tour will launch on the streaming service in the autumn but Andy said he did not have a show to go to when he decided to leave the BBC.
He said: "I didn't leave to go with Jeremy, we had nothing to go to. Nobody had called, it was just 'go'.
"The show compensated for everything. If we had a good show and good viewers, we were protected, but without that we were just left with this divorce hanging over us, so it was 'Let's just go our separate ways and see what happens'.
"It's a matter of public record that the BBC made a play for Richard and James but we wanted to stay together."
Jeremy was replaced by Chris Evans, who resigned after his first series, and co-host Matt LeBlanc, but Andy said he did not watch the new episodes.
He said: "I never watched it because there was a lot of pain for me, it was everything that I did. We gave everything to it. Also because I wanted to be able to say when I was asked if I had watched, that I hadn't."
However, he said he wished no ill will to the cast and crew of the show saying: "Chris Evans and everyone went to work to make it, I wouldn't wish them one second of ill that they wouldn't succeed. You can have two car shows and I hope they crack it."
He admitted he does not yet know exactly when the Amazon show will launch, or if it will be released weekly or dropped all in one go, in the style of Netflix releases.