Michael Cunningham has a fabulous essay at the NYT about the ways in which all acts of writing and reading are translations:
Here’s a secret. Many novelists, if they are pressed and if they are being honest, will admit that the finished book is a rather rough translation of the book they’d intended to write. It’s one of the heartbreaks of writing fiction. You have, for months or years, been walking around with the idea of a novel in your mind, and in your mind it’s transcendent, it’s brilliantly comic and howlingly tragic, it contains everything you know, and everything you can imagine, about human life on the planet earth. It is vast and mysterious and awe-inspiring. It is a cathedral made of fire.
And another snippet (Helen is a waitress, and devoted leisure reader):
I began to think of myself as trying to write a book that would matter to Helen. And, I have to tell you, it changed my writing. I’d seen, rather suddenly, that writing is not only an exercise in self-expression, it is also, more important, a gift we as writers are trying to give to readers. Writing a book for Helen, or for someone like Helen, is a manageable goal.
It also helped me to realize that the reader represents the final step in a book’s life of translation.
Well worth the time. (I'm at the stage of my current draft where I feel like I'm trapped inside the cathedral of fire, but there are worse places to be.)
Edited to add: See also the wonderful Tiffany's related post.