Shaun Edwards says he opted to leave Wales for France because they offered him twice the length of contract that the Welsh Rugby Union did.
The defence coach told Scrum V he was offered a two-year Wales deal.
Edwards, who has signed a four-and-a-half-year deal, is now preparing for France's 2020 Six Nations campaign.
"Most of my offers were around about the same money so it was purely down to the length of contract," said the 53-year-old.
Edwards' deal to join Fabien Galthie's France backroom staff was confirmed in November 2019 after 12 years with Wales.
He was part of a Wales coaching team that won four Six Nations titles and three Grand Slams.
Edwards added: "I've got two daughters and a son to keep - and if you get a four-and-a-half-year deal which is what I've always had before compared to a two-year deal, well there's obviously no choice really, is there?"
Edwards, a Wigan, England and Great Britain rugby league legend, had agreed a deal with Wigan Warriors in August 2018, but decided against joining the Super League club.
"I obviously didn't have a load of offers at first because everybody thought I was going to Wigan and then I didn't go to Wigan because of lack of control over what I felt was a head coach role," he said.
"That way of working has worked for Wigan before so good luck to them, but when I was head coach at Wasps I definitely had input into the people I was bringing on board within my coaching staff.
"For a while, I had no job on the horizon. But the last Six Nations went well for us all [Wales won the Grand Slam] and I got offered a few jobs after that."
Edwards is the most experienced member of Galthie's staff, which includes Laurent Labit, William Servat, Karim Ghezal, Thibault Giroud and Nicolas Buffa.
As the only non-Frenchman in the set-up, he is making sure he learns the language.
He said: "I give some orders in French, but if it ends up being too long of a conversation, I have William Servat to come and help me.
"But even in English, I only say three or four words on the bounce because when you stop and talk too much... it's not what we do.
"The coaches have definitely welcomed me. I've only known the players for four or five days so that's not long enough to assume anything, but the other coaches have been absolutely fantastic with me."
World Cup regrets
Edwards helped head coach Warren Gatland guide Wales to two World Cup semi-finals - but he laments their inability to reach the final, losing to runners-up France in 2011 and champions South Africa in 2019.
"We won four Six Nations titles, but I think we could have won about six," he said.
"We came second three times, so I wish we'd have won five or six actually, but I'm always greedy.
"Obviously not making it to a World Cup final is the biggest regret.
"We wanted to give the Wales fans who'd supported us so well over the years the ultimate game in international rugby union.
"We were one point away in 2011 and we were three points away in 2019.
"In three World Cups, we got knocked out by a combined total of eight points and that breaks you.
"It would have been great to be in a World Cup final. But to be honest, we'd had such a tough fixture list and we hadn't had a break like a lot of the other teams had. So I thought the boys did incredibly well to go toe to toe right to the dying seconds with the team who then became world champions."
France target England scalp and Wales reunion
France host England in the first round of the Six Nations on Sunday, 2 February and Edwards hopes to make an immediate impact, as he did with Wales 12 years ago.
In his first assignment, Wales won 26-19 at Twickenham - their first victory there in 20 years - and went on to win the 2008 Grand Slam.
"Each game is a different entity but it would be nice to replicate what we did with Wales in 2008," he said.
"We start off against a team that's just played in a World Cup final and a team that has been in the top four in the world regularly now for the last five or six years.
"England are obviously a team we want to get up there and compete with."
In the third round of fixtures, France head to Cardiff.
Edwards said: "It's always special going to the Principality Stadium and the game of rugby is incredibly important, but it's some of the relationships that I built and kept in Wales [that] go beyond the game of rugby.
"Caroline Morgan [Wales team personal assistant] and Alan Phillips [former team manager] and his lovely wife are such nice people and hopefully we can keep in touch for the rest of our lives."
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