Valtteri Bottas says he headed into the 2021 season a year ago knowing that his chance of staying at Mercedes beyond one more single-season contract was unlikely.
Indeed, Mercedes has promoted its newer long-time young prodigy George Russell to Bottas' seat for 2022, ending a five-year run of one-year contracts for the 32-year-old Finn.
Bottas has signed a three-year deal to switch to Alfa Romeo.
Recalling the months before he signed, Bottas said: "Toto (Wolff) knew that at some point we would have to make a decision.
"I knew that if I didn't manage to stay for the next two years or more, I would definitely try something new. Toto said there was not that opportunity, so in the end it was quite a simple decision for me," he added.
Lewis Hamilton made clear that he was unhappy with the call, especially after calling Bottas the best teammate he has ever had in Formula 1.
"That's quite disrespectful - what did I do wrong?" Hamilton's former teammate Nico Rosberg joked.
In fact, relations were ultra-intense between Hamilton and Rosberg - in total contrast to the subsequent garage atmosphere with Bottas.
"It was completely different to when I was there and Valtteri deserves all the credit for that," said the 2016 world champion.
Rosberg admits he knew the only way to beat Hamilton was to "get into his head" and "destabilise" the multiple champion, and hinted that one mistake Bottas made was to not make use of a mental coach.
"Mental training doesn't work for me," Bottas insists. "When I'm going through hard times, my first point of contact is the man in the mirror.
"I'm not Nico Rosberg - I'm Valtteri. And I know what's best for me."
Bottas' rookie teammate for 2022, the first Chinese F1 racer Guanyu Zhou, is certainly happy with the Finn's move from the front of the grid to Alfa Romeo.
"For a rookie, there is no better option than to have Bottas as your teammate in your first season," he said.
"He can help me get through the learning curve. He is a very open driver who shares information and discusses with the team and with me, which is really helpful.
"After all, there are only a few drivers who can out-qualify Hamilton, and he is one of them," added the 22-year-old.
