Williams technical officer and former Mercedes CTO Paddy Lowe has explained that after missing out on the F1 title in 2016, Lewis Hamilton got stronger than ever, which is why he's been unbeaten ever since.
In that year, Hamilton was pipped by his teammate Nico Rosberg, who won his only title in 2016. The German shocked the world by announcing his retirement from F1 only days later, causing Mercedes to sign Valtteri Bottas as his replacement.
Since then, Hamilton has won back-to-back titles, claiming his latest one in Mexico last weekend.
"The 2016 year was one he didn’t win and he probably believes he could have won it so that was a good motivation for him to understand how to strengthen his game," Lowe explained to F1i.
"And we’ve seen that the last two years."
The only real challenger Hamilton has had in 2017 and 2018 was Sebastian Vettel, but even the four-time champion couldn't get close to Hamilton in either year despite looking like the favourite earlier this season.
“We’ve seen Sebastian has struggled to beat him this year. There have been losses in all sorts of different areas but even just as a driver matching I think Lewis has outclassed Sebastian.
"That’s been one of the mismatches, there have been other mismatches in terms of the teamwork.
"One team has performed better than the other team top to bottom. But on top of it all is Lewis who’s just a phenomenal driver.