If you find books via the internet, you’ve probably already begun to use email recommendation services such as BookBub and Pixel of Ink to help you find deeply discounted ebooks (and sometimes paperbacks).
There are several of these services out there. From a writer’s point of view, I look for the ones with the largest subscriber base, to get the biggest bang for my buck. BookBub owns the title of largest with somewhere around 2 million subscribers. But, some users have become rather ho hum over the offerings provided.
See, if these services begin recommending books the subscribers buy and then find to be poorly written or wrongly recommended, the service looses its value and authority.