Why does Phaeton lose control of his father's chariot?

Phaeton, son of the Sun God was, in many versions of the famous mythology, was a selfish and spoilt boy. He had asked his father if he could drive his chariot, and his father said no. However in one version of the story, his foolish mother sided with him. Apollo finally gave in, yet warned Phaeton about the dangers of speed, devils and monsters and the heat of the stallions and chariot. Phaeton ignored this of course, being the boy he was, and proceeded up-nosed.

Eventually, as Phaeton started on the course of the sun, he began to get impatient and he whipped the horses. From this idiotic move, the horses reared and headed far, far up into the sky, causing the land below to freeze and animals to run in fear. Phaeton let loose the reins and the stallions went hurtling downwards.

His sisters blamed the problem on their selves and Zeus took pity on their weeping expressions. He turned them to weeping willows.

Okay, I know I gave all of the story, but you might as well know.

READ THIS NOTE FIRST!

If you want a straight answer go to the SECOND paragraph