Driving is generally on 4 wheels whereas cycling is generally on 2. So you can't "fall off" your car, like you can on a bike. Also the tyres are much wider on a car, giving a bit more grip.
I didn't mean one's own safety, I meant the safety of those you might skid into in a car, despite the extra grip. Rhyl and Looe are two names that come to mind.
Yebbut screw them - if they wanted to be safe, they should be in a car, right?
I've skidded in a car (grew up out in the villages, commuted across the wilds of Norfolk for a couple of winters) and I've skidded on a bike. If you take it slow and control it, it's not as scary as you might think, but I've no desire to repeat either. Given the choice, I'd skid on the bike - I've so much more road width to play with compared to my width that I suspect I'm less likely to collide with stuff - and less-skid-prone studded tyres are allowed on the bike and not the car, so I think it's an obvious choice: I'll take the bike. By far the main danger are the horrible motorists who are not only still choosing cars, but seem to be driving as if the roads are dry, but at least on a bike, I can take routes mostly away from them, whereas in a car, I'd have to mix it with those dangerous people all the time and the way they're going, I don't think a car's airbags and so on would be sufficient protection every time.