Lewis Hamilton has to take a long hard look at himself.
He once again made a silly mistake, and it not only spoiled his race in Singapore, but it also ruined Felipe Massa's as well. By touching the back of Massa's Ferrari with his front wing, he punctured the right rear tyre.
The Brazilian had every right to be angry with him after the race, especially considering he had been the victim of another reckless move from Hamilton in Monaco in May.
Yes, Hamilton drove well after the pit-stop to change his damaged front wing and the drive-through penalty he received for the incident, but he should have finished higher than fifth. Being over ambitious cost him dearly.
It was another misjudgement from the Briton and it has to stop.
There was never going to be enough room for him go down the outside of Massa in his McLaren-Mercedes as they braked at the end of the long straight. Hamilton should have backed out of it but, instead, he stayed wide, judged his braking point incorrectly and hit the rear of Massa's car. It was a maneouvure which ruined any chance either of them had of making the podium.
If this was just a one-off then you would say it was a simple driver error, these things happen, and you would move on.
But this is about the fifth or sixth major mistake that he has made this season and it is becoming a real concern.
It must be frustrating for Hamilton, because it is frustrating for me watching him at the moment. I am sure his supporters across the world feel the same way.
I know he has said he is only in Formula One to win, and it must be difficult for someone as ambitious as Hamilton to watch Sebastian Vettel cruise to his second title at the age of 24. It wasn't so long ago Hamilton was the man of the moment after missing out on the championship by a point in his first year, and then winning it in his second season.
But overdriving your machinery and taking a lot of risks in an attempt to try keep pace with Vettel and Red Bull Racing is not the way to go about things.
It is not just about the fact he is not winning and is not in the contention for the championship this year that is bothering him.
The form of Jenson Button has rattled him. Button is arguably producing the best driving of his career, and he is outperforming Hamilton.
Hamilton has never had this situation before where he is getting regularly beaten by a teammate.
When he partnered Fernando Alonso in 2007 he was expected to play second fiddle but he surprised everyone by being on the pace immediately. It ended up being Alonso who was struggling to cope with the situation.
Now Hamilton is up against it with a teammate who is pushing him hard. Button has beaten him in the last four races.
Button is doing a good job because he keeps himself out of trouble, does not get involved in incidents with other drivers, and that allows him to fulfil his potential when it comes to results - something that Hamilton has not done this year. That is why he is behind his teammate in the drivers' standings.
There has been speculation where Hamilton's future lies but his options look limited.
I am sure McLaren would want to keep him, but their loyalty might start wavering if he keeps making such costly errors.
Hamilton will be glad when this season is over in November in Brazil. He needs to take a step back, look at the incidents he has been involved in and try to learn from them and move on. Otherwise he is danger of ending up with just one championship title to his name when his career is over. Which is something I know he is desperate to avoid.
Johnny Herbert is a former F1 driver with three career victories. His column is written with the assistance of staff writer, Graham Caygill