Williams tech boss Paddy Lowe believes Lewis Hamilton's defeat at the hands of Nico Rosberg in 2016 provided the Brit with a big dose of motivation for the following two seasons.
Before moving to Williams at the beginning of 2017, Lowe worked alongside Hamilton at Mercedes where he headed the German outfit's technical department.
The engineer offers his assessment on his former driver's path to his fifth world title.
"I think he’s driven two terrific seasons," Lowe said. "Two of his strongest seasons of all these last two years.
"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. And we’ve seen that the last two years."
While 2018 runner-up Sebastian Vettel certainly gave Hamilton a run for his money, and his mistakes notwithstanding, Lowe believes the German just isn't a match for a man who almost appears unassailable as he sits at the top of F1's mountain.
"He’s become a very difficult driver to beat," insisted Lowe
“We’ve seen Sebastian has struggled to beat him this year. There have been losses in all sorts of different area 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.