Some believe the British outfit chose the Russian over Robert Kubica or another option for 2018 because of the millions in backing he brings.
But boss Claire Williams insisted: “We have been giving young talent a chance for a few years now and have always done well with it.
“I can assure you that if we had the slightest doubt, we would not have taken him,” she is quoted by Auto Motor und Sport.
Williams said a good example is Sirotkin’s teammate, Lance Stroll.
“Lance was not given any credit and then he got 40 points and was the only driver outside the top three teams to make it to the podium,” she said.
So Claire Williams said the team got lucky in finding the opportunity to sign Sirotkin.
“He is one of the talents who have been developing very well but quietly,” she said.
So she said the ‘pay driver’ label is “unfair”.
“What is a pay driver anyway?” Williams asked. “A driver who brings a sponsor? Then Fernando Alonso is one too.”
Williams technical boss Paddy Lowe agrees: “We spent a lot of time analysing the drivers, and the data decided.
“And believe me, the people who analysed the data did not know who’s bringing in what amount of money.”
The 2018 Williams is the first car design Lowe has had full control of, but he insisted it is really the “product of a great design team”.
“We were two seconds from the top teams last year,” Lowe said. “That deficit has to be drastically reduced now.”