I've been reviewing books and posting online now for about 2 and half years. I originally did it just because I read a lot and originally was posting basically every day about how far I had got with the latest books and what I thought of it so far. I did wonder if authors would be interested in how a reader's impression of the book changed as it went on.
That then moved to a more traditional read and then review. Mostly this was just because of the amount of time it was taking to post every day (and sometimes things get busy in real life), but also because it felt like posting every day was somehow chipping away at the final result. Although if any authors do want a day by day post of how I find their book I'm sure I would be happy to do that.
One thing I didn't expect was just how much reviews are treasured by (most) authors. I write my reviews on Goodreads, which automatically posts to Twitter for me (I'm not a big Facebook user these days). I then run through my reviewed books in sequence and repost any 4 and 5 star reviews to Twitter, trying my best to find the author's Twitter handle. I didn't expect anything really from the authors (especially of volume published books) but usually I get a like if not a retweet. If I am very lucky the author will message me and some authors I've become a huge supporter of because they take this time.
But from their point of view reviews are the only way they have of knowing if people are actually enjoying their work (or not - criticism where it's justified can be just as valuable if a little demotivating). Pure sales or download figures can't do that. I just didn't realise how few people post reviews when they have read a book. In these days of social media sites for everything is it really that hard just to go on Goodreads and rate the book if nothing else?
So now my reviews are posted not only for me to compose my thoughts on the book I have just read. They are also for all you authors out there who work hard to produce great stories for us to read.