Well, how can one speak about some thing's author, the person who has built it from scratch, as of someone who can ruin it or not?

That said, it's hard for me to read her in English, and I've read HP mostly in at least three translations to Russian, one official and two unofficial ones. The former sucks, and from the latter two the one which reads the best is by the least professional translator (actually she's not a translator at all), and I mean Maria Spivak (the original one to circulate in the Runet and samizdat versions, not the abomination published much later).

It communicates the feeling of mad and a bit hooligan-ish fairy tale, I suspect that emotionally it's the closest to the original.

Anyway, it's pretty normal for an author to have a magnum opus and the rest of their works to just not make sense.