Really easy. You know how gazelle's get chased by lions?
Well, what if gazelles had evolved wheels instead of legs? That means that lions would also have to evolve wheels, because if they didn't, the gazelles would win a 'race' every time, and the lions would die. So, let's assume that now, gazelles and lions have wheels instead of legs. Now that the lions have wheels, they are faster than every other animal. Let's call in the zebra, also an animal hunted by the lion. To not get hunted to the point of extinction, zebras would also need wheels. Since zebras are related to horses, it would be normal to assume that if zebras had wheels, horses would also have wheels instead of legs.
So, there we go, a horse with wheels. What next? A class-action suit against Ferrari for plagiarizing the horses' invention. And nobody wants that, especially God, so he said:"Fsck dem wheels!" :laugh: