Most authors, we read, and that's about it. They produce the words and we consume them like we're slurping down so many yards of some restaurant's house-recipe pasta.
A few of them, a very small Elect, seem to be whispering right into our ear and our ear alone. The authors in question will vary among us, but the effect is the same: we feel, without an explanation being possible or even needed, that they are talking to us through the pages and right across time's walls.
My own list of such authors is as esoteric as anyone else's: Hubert Selby, Jr.; Ryūnosuke Akutagawa; Dostoevsky (reading him in a good translation was like discovering an entirely new author); Philip K. Dick, whose Electric Sheep? inspired me to say to my brother "I think I've found the first writer who understands how I see the universe"; maybe Theodore Sturgeon, too; and a small fistful of others.
Then there are the authors I have wrestling matches with. Authors which I do not exactly hate, but which I cannot help but argue with at almost every line, because they may be brilliant writers but espouse world-views or social theories way the heck out of phase with anything I could call my own. Mishima was like this; Heinlein; Henry Miller; William Burroughs; Céline (somewhat mitigated at this point, I admit).
Both parties are indispensible. Sometimes, you need to someone to tell you something you already know deep down, in words you'd never think to use. Sometimes you need someone to tell you something you never wanted to hear, and in a way that could seem like the only truth there is.