McLaren made too many mistakes this year to be able to launch a serious title challenge against Red Bull Racing, reckons Jenson Button.
With Sebastian Vettel on the verge of clinching his second world title, Button thinks that his squad failed to capitalize on the opportunities it had throughout 2011 to win more races.
"Seb has got a great car underneath him and has done the perfect job with it," said Button in Singapore. "When someone is in that form and the car is working like that and the team doesn't make mistakes, it is very hard to beat them when you don't have one of those aspects.
"For us, we have made too many mistakes this year and we haven't quite gotten it together on a race weekend, even when we have had the performance. So that is something we have got to work on, and something we are working on.
"If you look at the last few races, if everything had gone well then we would have had a really good chance of fighting Seb for the win. But we haven't done a good enough job. He has done a very good job this year and I am sure he is proud to be World Champion, which I am sure he will be in the next few races."
Button believes that Red Bull Racing has benefited from being well-resourced, which is why the team has been able to maintain its form throughout the campaign, unlike during his title campaign when Brawn GP fell back over the course of the year.
"They have the resources that we never had," said Button. "We were not able to really develop the car throughout the year I won the championship. That is why we could not be consistent.
"With Red Bull, they have resources to keep developing the car. And their reliability has been amazing this year. Their first non-points scoring race this year was Mark [Webber] and that is because he crashed, so they have been untouchable at a few races this year, and at others we just have not matched them in terms of doing a good job."
Button also says that his team is focusing on making improvements to its starts, after losing places off the grid at Monza last time out.
"My clutch was contaminated at the start," explained Button. "I had oil on the clutch so that is why I had a bad start. It is the first time it has happened this year, and that is the reason I lost so many places.
"Our starts in general are, I think, OK compared to Red Bull, quite similar, but compared to Ferrari we are definitely behind. There is not a lot of room here to overtake into Turn 1 which is good.
"When you have circuits that have a long drag down to Turn 1, it is very difficult for us to hold off a Ferrari if they are right behind us. So you do all the hard work on Saturday, and then you get overtaken into Turn 1. It is an important area and something we are always trying to improve."