An author shouldn't have to blow his own trumpet. It's demeaning. A book should speak for itself. It should be all about the writing, not the author. However,it seems that in this modern age a book by an unknown author has no chance of being discovered if left to itself,without publicity,whether this publicity comes from the publisher or the author or both. So unknown, struggling writers find themselves having to do all sorts of things they'd, perhaps, rather not be doing in order to publicize themselves as authors in the hope that it will get them more sales. And the authors who are best a this game of self promotion will succeed over those others who are not so good even if their actual work - ie their book - is the less accomplished. So a book's commercial success is not necessarily an indication of it's merit. Lucky the author who manages to write a book that is worthy, that has merit and is also a commercial success!