As someone who collaborates and occasionally ghostwrites books -- the difference most of us draw is whether our names are included on the books -- I can tell you that most sports autobiographies/fitness books/business motivational tomes are produced by professional writers whose job it is to draw the material out of the expert/celebrity/prominent person and write the book quickly and effectively.
Macca, like most successful people, does not have the time to write a book himself. Fortunately there are enough of us out there who can do the heavy lifting quickly and effectively. In that sense, it's no different than home improvement projects. There are many things I know I
could do, but it would take me three times as long and the work would not be as good as that done by a professional contractor. Better to focus on one's core competency.
The problems come when the subject either does not give the writer enough time/information, resulting in a flimsy book, or fails to review the drafts. That's how you end up with someone like Charles Barkley or David Wells, who claimed they were misquoted in their own books. They weren't. It's just they didn't bother to review the drafts of the books and say, "You know, what I said was a little harsh. Let's change that."
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