Because the great thing about fairy tales and folk tales is that there is no authentic text.
(…)
One thing that did strike me was how different these stories are from novels. You almost never see an adverb—”he said ruefully”—anything like that. That doesn’t happen. You just get what he said, what she did, that absolutely bald statement. And I like that. I wanted to avoid what some modern tellers have done, quite legitimately, to make them more like novels and short stories, to characterize the heroes and the heroines much more than they are characterized in Grimm. I like the psychological flatness of them, the fact that they’re more like masks than individuals.
Philip Pullman, sobre a sua versão dos contos dos irmãos Grimm
Isidora Works 