There have been a couple of stories recently about so rather famous authors reviewing their own books. Of course the authors in question gave their own books great wonderful reviews. Books that weren't their own they in turn gave bad reviews to. First thing I'll state is that I don't know if I could do that, it just seems wrong to me. The authors in question were even traditionally published. They weren't independently published like I am. Quite a violation of the code of conduct that supposedly exists but obviously doesn't.
My own experience is originally as a book reviewer before I became an author. I've reviewed a lot of books in the past, I'm still reviewing them and will continue to do so far into the future. You can even check out my Amazon and Goodreads review profiles.
163 reviews total on Amazon alone, 68 reviews on Goordreads. That’s a lot of reviews and in Amazon's case that’s over two and a half year’s (since March 21, 2009). The majority of those are for books. At one time I was even a part of their Vine program. If you look through the posts on this blog you'll see a number of reviews I’ve posted also.
Why I will continue to do them is because it forces me to read at least some everyday. By reading every day I conversely become a better writer. I may not be the best writer right now but I wouldn't be as good I am now if I hadn't read as much as I have. It's always a good experience to get outside of yourself and experience someone else’s viewpoint.