"It is a time when I needed a change and it's at an important moment in formula one when everything is changing."
With similar reasoning for departing Williams, however, is Xevi Pujolar, a long-serving engineer who has quit the team to join Toro Rosso.
"Last year," he told Spain's El Confidencial, "the situation was quite difficult and Williams did not feel right. So I decided to change.
"When Pat Symonds arrived I was fine with it because he is someone with great experience, there were other factors as well.
"I had spoken several times with Toro Rosso and it looked like a growing team with great potential."
Spaniard Pujolar, 40, said part of the problem at Williams was its difficulty in adapting from life at the very front of the grid.
"You have to accept that times are changing and make different plans," he said. "And accept that you're not world champion anymore.
"But now I think they are making many changes and will improve. Personally, I needed a change of scenery."
Finally, Pujolar laughed when asked if he would change places with a Renault engineer at present, given the French marque's current technical troubles.
"I think I'm fine where I am!" he said.