But they may not be ruled out. My younger brother loved cars, at the age of 10 he was about 5'5 and used to beg my parents to let him back their cars out of the garage. We had a place in the middle of nowhere and my parents would let us drive because there were no other people around. He was a good driver and still continues to be one, (written test aside) he would have passed his driving test no problem. However he did have 10 year old moments, moments that rarely run through an adults mind and if they do most adults do not act on them. He would suddenly turn the wheel to chase after birds on the ground, imagine he was racing, forget he was the one driving...etc Now in just 5 years he's changed so much, he still does stupid stuff and is still quite irresponsible (which is why he has no car and no permit), but he no longer chases birds with the car or races his imaginary friends. While there are many mature 10 year olds few if any are free from having 10 year old moments. 10 year olds can't drive for the same reason I can't rent a car, the law picked an arbitrary age that it feels most people have reached the minimum requirements for doing something at, and even if you're ready sooner, it's tough cookies you can wait, like everyone else has to.