Dr Seuss made every word count. And what words! Once read, they bounce around inside your head like a bagatelle. There's the story of how Ted Geisel (his real name) was receiving an honorary degree from an American university and the graduating students all stood up and recited from memory every single word of Green Eggs and Ham in his honour. What a tribute.
But those words didn't come easily, as Geisel explains:
You can fool an adult into thinking he's reading profundities by sprinkling your prose with purple passages. But with a kid you can't get away with that. Two sentences in a children's book is the equivalent of two chapters in an adult book.
For a 60-page book I'll probably write 500 pages. I think that's why it works. I winnow out.
(quoted in "Dr. Seuss's Green-Eggs-and-Ham World," by Judith Frutig, The Christian Science Monitor, May 12, 1978)
He called this process 'meticulosity', a lovely Seussian word. It sums up the process of writing and a writer's need to expect the highest standards of himself, not accepting second best.
Plenty more to read, here.