I’m not the biggest Cormac McCarthy fan, but I saw a reference that he would turn down requests to discuss his works on college campuses, saying that he had said all he wanted to in the books themselves. “Everything he had to say was there on the page.”
This authorial reserve is rare these days. I’ve met a few authors, W. P. Kinsella, who was pleasant, Lois McMaster Bujold, who simply read from her novels, and Roger Zelazny. I also met Alasdair McIntyre, but I’m only counting fiction writers. Zelazny was the most interesting. I was a young man at the time working my way through the Amber novels, and I mentioned how it would be good for him to have a synopsis of what had gone before in front of each novel, since I was thoroughly confused. He smiled, said “Good!” and signed my book.
If you are a writer of fiction, your art is in the book. Let it speak for itself. As a counter-example, see J. K. Rowling, who can’t stop retconning her own work. Leave it alone! Writing is an elliptical art, leaving as much unsaid as said. The reader, at least the good reader, makes most of the experience of the book by him or herself. The gaps that the author leaves are where you come in. If the author tells you too much what the books mean, the experience is ruined.
In addition, as Socrates complained in the Apology, often the poets don’t really know what they mean anyway. The greatness of the book exists in spite of them, not because of them. “Rage, sing Muse the rage of Peleus’ son Achilles!” The Muses are real, and they don’t like it when you try to peek behind the curtain.
By the way, Kinsella’s works are nice, Bujold is worth reading, and Zelazny reached a peak in Lord of Light.