If all of the story is there, one might ask, then why bother? Isn't it just indulgence after all? It better not be; if it is, then I have spent a large portion of my life wasting my time. As it happens, I think that in really good stories, the whole is always greater than the sum of its parts. If that were not so, the following would be a perfectly acceptable version of "Hansel and Gretel":
Hansel and Gretel were two children with a nice father and a nice mother. The nice mother died, and the father married a bitch. The bitch wanted the kids out of the way so she'd have more money to spend on herself. She bullied her spineless, soft-headed hubby into taking Hansel and Gretel into the woods and killing them. The kids' father relented at the last moment, allowing them to live so they could starve to death in the woods instead of dying quickly and mercifully at the blade of his knife. While they were wandering around, they found a house made out of candy. It was owned by a witch who was into cannibalism. She locked them up and told them that when they were good and fat, she was going to eat them. But the kids got the best of her. Hansel shoved her into her own oven. They found the witch's treasure, and they must have found a map, too, because they eventually arrived home. When they got there, Dad gave the bitch the boot and they lived happily ever after. The End.
I don't know what you think, but for me, that version's a loser. The story is there, but it's not elegant. It's like the Cadillac with the chrome stripped off and the paint sanded down to dull metal. It goes somewhere, but it ain't, you know, boss.