Often something comes in from which you can see that the person is good, the book may not be perfect as it is, and the person doesn't want to do a re-write. That's something we do almost nothing of.
As far as I'm concerned, there won't be a Beatles reunion as long as John Lennon remains dead.
Ideas improve. The meaning of words participates in the improvement. Plagiarism is necessary. Progress implies it. It embraces an author's phrase, makes use of his expressions, erases a false idea, and replaces it with the right idea.