Casemiro believed his time at Real Madrid was coming to a natural end as the midfielder shot down suggestions his move to Manchester United is is financially driven.
The 30-year-old will complete his transfer from LaLiga champions Madrid to the Premier League this week after he was handed a hero's farewell at Santiago Bernabeu.
Casemiro makes the switch to Old Trafford in a transfer thought to be in the region of £60million (€70m), as United splash the cash in the wake of a dismal start to Erik ten Hag's tenure.
It will see Casemiro switch from a team out to defend their Champions League title to one that might be struggling to make Europe by the end of the season.
But he is relishing the challenge, and believes it was the right moment to call time on his Madrid career.
"My cycle here is finished," he stated. "I am looking for new challenges, new goals, [to] experience a new culture, [to] live in a different city.
"I haven't won anything there yet, I will be just another player looking to help the team. The main reason is the new challenges and wanting to do something new in my life.
"I've become a father here, I've spent nine years here. People who know me, know it's not because of money. If it was, I would have left much earlier, but it's not that.
"It's my decision. The club has supported me, but people who think those things are people that don't know me and they are wrong. The last thing I think about [is money]."
During his time at Madrid, Casemiro won 18 major trophies, including three league crowns and five Champions League titles, and his decision to step away was a hard one.
"I'm very happy when I think about everything I've done here," he added. "I feel I did the job that I was expected to. I've always tried to give my all, [and] I'm very happy for everything that I've achieved here.
"It's always difficult to take such a decision, considering how many years I’ve spent here, how much I'm loved and how happy I was here, but I was really sure about my cycle here being over. I've already made history here and achieved everything that I wanted to achieve, and now it’s time for me to think about new challenges."
Casemiro also revealed his decision was a long time in the making.
He explained: "After we played the Champions League final I talked to my agent. I felt that I was finishing my cycle here. I've always been very honest with myself, the president, the fans and I felt that my cycle was coming to an end at Real Madrid.
"I went on holiday, deciding to relax and to see what happened, and when I was back I still had that feeling. I'm extremely happy because of everything I've done here and I feel that I did what I had to do. History was made, and it was made in the right way."