When it's on target, a simile delights us in much the same way meeting an old friend in a crowd of strangers does. By comparing two seemingly unrelated objects, a restaurant bar and a cave, a mirror and a mirage--we are sometimes able to see an old thing in a new and vivid way. Even if the result is mere clarity instead of beauty, I think writer and reader are participating together in a kind of miracle. Maybe that's drawing it a little strong, but yeah--it's what I believe.

Stephen King