Button says Vettel just lucked into his win...

[Scott]

I completely agree.  Vettel rolled the dice by joining Ferrari while it was in turmoil, but somehow something good was going on behind doors and they brought a better car this year.  He had to not make any mistakes and manage his tires properly, and needs to get credit for that of course (and of course have Mercedes make a few blunders). 

Alonso's luck when he rolled the dice for Mclaren was all bad, at least so far.

But of course Button knows about good and bad luck and being in the right place at the right time.  Brawn F1 - One Year Wonder...

http://thisisf1.com/2015/04/01/cannot-take-too-much-credit-vettels-struck-it-lucky-at-ferrari-button/

[Jericoke]

It's been a long time since we could say a champion, or even a race winner, won by pure skill alone.  (Certainly when it comes down to teammate battles, Vettel and Hamilton have shown themselves capable)

It takes a lot of being in the right place at the right time, and a certain amount of mistakes from other teams/drivers.

However, I think being able to spot which teams are prone to mistakes and which ones are getting ready to make the next step is part of the skill of an F1 driver.

[F1fanaticBD]

I think he knows all about more than anyone else in the wrong team. His debut was in Williams to Benetton, when he left that Willams was winning with Juan Pablo & Ralf Schumacher. He left Renault for BAR, and Alonso won there 2 WDC. You have to remember, he was almost in the verge of loosing the race seat in 2009, but like a miracle he became WDC.  Also after he joined Mclaren, its not been upward curve either