In The Montessori Method, Dr. Maria Montessori wrote:
[Children] are not understood, because the adult judges them by his own measure: he thinks that the child’s wish is to obtain some tangible object, and lovingly helps him to do this: whereas the child as a rule has for his unconscious desire, his own self-development. Hence he despises everything already obtained, and yearns for that which is still to be sought for. For instance, he prefers the action of dressing himself to the state of being dressed, even finely dressed. He prefers the act of washing himself to the satisfaction of being clean: he prefers to make a little house for himself, rather than merely to own it. His own self-development is his true and almost his only pleasure.
To have learned something is for the child only a point of departure. When he has learned the meaning of an exercise, then he begins to enjoy repeating it, and he does repeat it an infinite number of times, with the most evident satisfaction. He enjoys executing that act because by means of it he is developing his psychic activities.
The same exercises are not repeated by children of all ages. In fact, repetition corresponds to a need. … It is necessary to offer those exercises which correspond to the need of development felt by an organism, and if the child’s age has carried him past a certain need, it is never possible to obtain, in its fulness, a development which missed its proper moment.
(pp. 356-358, The Montessori Method by Dr. Maria Montessori, trans. Anne E. George, (c) 1964 Schocken Books, New York (and (c) 1988 Random House), ISBN 0-8052-0922-0)
Repetition is important for developing memory and a functional subconscious, I would think, but it is undoubtedly important for developing a conception of causality — which is very important knowledge (whether implicit or explicit) for living, for attaining values, in this world.
Interesting also how the child is driven to automatize the actions, skills and knowledge necessary for living in his or her environment. And how these things are hierarchical: he builds skill upon skill and knowledge upon knowledge; without some skills/knowledge developing, others can’t happen.
Repeating the skills and actions over and over again makes them automatic and allows the child to focus and learn other things.
I think that, at a young age, children are (generally) doing what needs to be done to develop their potential, precursor rational consciousness into an actual rational consciousness. It takes work to make the potential into the actual.