Promoting his autobiography Ordinary Joe in an interview with The Daily Telegraph Schmidt said: "I'm not sure I'll ever go back to coaching.
"I just don't know. I want to give myself a bit of distance. I'm emotionally attached. I do take it home with me."
The impact of the quarterfinal 14-46 loss to the Al Blacks had been a bitter pill to swallow. He had talked little about it since the post-game press conference and felt the loss was still raw.
"I do feel a sense of responsibility to the people who support us, the people who came out to Japan, the people whose hopes we may be inspired. To let them down was…really tough," he said.
He had taken comments made by Isa Nacewa, with whom he worked at Leinster, and former Ireland captain Brian O'Driscoll, after the World Cup hard.
He had always maintained a lower profile than many other international coaches.
He said he had always been guarded about his personal life.
"Ever since my time with the Blues. That was tough going. When your 10-year-old son comes home from school in tears because people are saying his dad is no good…I mean, he was always going to find out one day but that was a bit early!" he said.
Schmidt said in hindsight his biggest failure was focusing too much on the World Cup but he felt there was nothing wrong with Ireland's game play.
"You're learning all the time. And that's one frustration I'll have with not coaching any more," he said.
Schmidt said he wasn't planning to coach seriously.
"But it's not like coaching in football where you can potentially accumulate enough to retire permanently. I'll have to go back to work at some stage. I'm just not sure what that will look like," he said.
Whatever else happened, Schmidt would be regarded as the greatest coach in Irish rugby history.
He had been offered jobs both in Europe and New Zealand, with a couple of them left on his phone immediately after the loss to the All Blacks in Japan.
"So, at least, as broken as you are, people don't see that your value has completely gone because you lost a game. I'm really not sure what the future holds," he said.