The more items you put on a shelf, the more ways the items on the shelf can be arranged. The difference between 4 items on a shelf and 10 items on a shelf is exponential in terms of the number of ways they can be arranged.
The same is true for knowledge and creativity.
That matters, because we live in a world where brains are more important than brawn.
P.S. The first paragraph is paraphrased from a book I read, but I don’t remember which one.