Jenson Button says he contemplated his future in Formula 1 during a troubled 2015 campaign with McLaren.
Button was retained over Kevin Magnussen at the end of 2014 but the renewed McLaren-Honda partnership led to the Briton questioning his place in the sport, before he ultimately opted to stay on for 2016.
"Last year I wasn't sure if I'd be racing and it wasn't my choice," Button told Sky Sports, referring to McLaren deliberating over his future.
"This year it was totally my choice and there was a moment where I thought 'I am not sure I want to do this anymore and be where we are.'
"Obviously, if we are where we are right now next year, it is not going to be that enjoyable.
"I spent a lot of time with the engineers and the aerodynamicists and I spoke more with Ron [Dennis] in the two months when I was trying to decide what to do next year than I have in my whole time at McLaren.
"We went through a lot of ideas for next year and spoke to the aerodynamicists and the engineers and got a real direction and understanding of where we are going and with Honda as well.
"So that got me excited, that got me pumped for next year knowing that there are big improvements on the horizon - and we need them."