Note how in the early books they mention how careful Perrin is, because of his size and strength. Egwene, being small and female, would never have had to learn lessons like that. When young Perrin gets in a confrontation, he backs down or gets told "pick on someone your own size." When a small person gets in that situation, they have the oppositte experience. Younger children tend to receive much less discipline than their older siblings, because the parents are used to the ideas of their babies growing up and learning to function, and because they are tired of fighting the same battles with each kid. By the time the youngest hits her teens, Mom & Dad are basically going "Fuck it. What's the worst that can happen?" In a village where everyone is into everyone else's business anyway, a kid can't get into too much trouble, and with the family business being inn-keeping, her chores and responsibilities were basically ordinary daily tasks only expanded in scale. Farm kids would have had to learn to take care of the farm, and bust their humps and take responsibility (even Mat is only irresponsible by comparison to the super-conscientious Perrin & Rand). Their wills are curtailed by mother nature, whereas Egwene's example would have been Nynaeve who appeared to make nature bend to her.
In short, Egwene would have grown up unrestrained or curtailed in her basic behavior patterns (also, more likely to end up a homosexual, BTW), and at the same time, being among the least in many ways, would have come by her craving for power quite naturally.



Not to mention, we see how well she takes criticism, or even people arguing a contrary point of view. The girl who unilateraly decided Rand needed to be taken down a peg for his own good, because he had the audacity to expect his soldiers to obey his orders, who used their aquaintanceship to barge in on him and make a big production out of her refusal to acknowledge his rank or stature, orders beatings for girls who make faces at her on exactly the same terms she used to tell Rand to wash his ears. When she has her flip-flop on the subject of the Three Oaths, she gratuitously threatens punishment for the two people who have done a far better job of living up to them than she did. One day she's challenging Nynaeve for agreeing to do her best to live up to the Oaths, contrarily asserting her intentions to use the Power as weapon when she damn well wants, and ridiculing her for her attempts to avoid lies, and then when Nynaeve merely asks if she's thought about that topic, she's cutting off all conversation with an imperious gesture and threatening punishment for disobediance to a rule they have just found out cuts your life in half.

Mommy & Daddy's homespun wisdom does not have a chance.