Whether it’s a new food being introduced or a friend moving away, children face change frequently. Structure and routine provide children with a sense of security and predictability allowing them to develop a sense of mastery over their lives. Once that sense of mastery is strengthened they are capable of handling bigger challenges.
A child's behavior is usually reflective of their state of mind. A chaotic home manifests in the child's behavior and the child is more likely to be agitated and unsettled. Meanwhile, structure helps children organize themselves and their thought processes allowing them to have the cognitive space required to learn new things.
Similarly, regular routines help children get on a schedule. They are able to fall asleep more easily every night or feel hungry at about the same time every day. Knowing that changing in to their pajamas after dinner is ‘normal’ helps them cooperate, eliminating the need for constant nagging and power struggles. It also allows for a consistency of expectations from the parents without having to give allowances like skipping a bath or brushing their teeth to accommodate time constraints resulting from tantrums.
Once the rules have been internalized, children learn to enjoy themselves within the confines of those rules. For example, the child knows that she may not have time to play with a favorite toy in the morning before school but can place it somewhere accessible because she knows that there will be enough time for her to play with it as soon as she returns home.
This doesn't mean that there has to be a rigid routine that can never be changed. Times when the child can have another story at night or watch two shows instead of one are special occasions that children look forward to. They begin to truly value and appreciate those special treats.
Most importantly, children like being independent and as they grow older they learn how to follow the routine without constant reminders, it helps them feel competent. This translates in to adolescents and teens who have internalized the ability to structure their own lives and are therefore less defiant and rebellious.