When I first published a children’s books with Ingrams I researched 300 blogs and asked them for a review and 20 replied and I sent them a copy and never received a single review. Books did appear on ebay though selling cheaply. I have posted out dozens of books and once or twice received reviews – in good US journals – and I paid to have a book showing as an independent publisher in the new York Review of Books. Nothing came of it, The goodreads giveaways resulted in reviews of around 3.8 -4.4 out of five but no sales.
The books that sell well are those where the authors are out in the world promoting themselves.