I used to know someone who was generally accepted as the cars and driving expert of his friends. The group of friends all worked at various rural pubs in the kitchens. One had just got a new car, and asked his car expert friend, who had popped in for a pint, to take it for a spin, so he did.
He was driving on a route that he drove every day and hardly ever saw anyone else on the roads. He was driving well as far as he saw it, but fast - he was putting the car through its paces, after all. He was slightly tipsy, he had had about two pints, but had driven like that loads and felt ok.
A family car was on the same road, also going too fast. Mum, dad and two kids. The kids were messing about and wouldn't put their seatbelts on, the dad was driving and turned round to tell them off, straying on to the wrong side of the road for a couple of seconds.
At least thats what was guessed was happening inside the car. Nobody will ever know, because everyone died when the car expert whizzed round the corner, far too fast, into the family car going a bit too fast on the wrong side of the road.
I bet everyone thought they were a good driver. Individually, those things had happened countless times, but you never know when your bad driving behaviour will come up against someone elses bad driving behaviour.