The German shocked the F1 community when he announced his retirement shortly after narrowly beating his team-mate, Sir Lewis Hamilton, to the 2016 crown.
In an interview this week, Rosberg said he wanted to avoid exiting the sport as a has-been and would rather go out on a high.
“I wanted to avoid going out as a has-been or someone who is not wanted anymore,” Rosberg said.
“I mean, there was $100m on the table that I gave up on. I longed for a different kind of life. You don’t have flexibility when you’re racing.
“It was the best decision for my family – I didn’t think about the money for one second,” he added.
Commenting on the rivalry between him and Hamilton, Rosberg recalled getting booed by ardent fans of the Brit, including a group of four-year-old girls.
“There were the two camps, the Nico camp and the Hamilton fans. And all the Hamilton fans were against me, of course,” he said
“[On one occasion], there were these four-year-old girls right in front of me with their dads, and they were booing me and giving me the thumbs down. Their dads told them I was bad and that they needed to boo me.”
Since quitting Formula 1, Rosberg has focused his efforts on being a sustainability entrepreneur, with him investing in a number of green projects.
The German also recently founded his own Extreme E team for the series’ inaugural season this year.