*Marketing people are looking for products that are easy to sell. They don't want to have to work to sell an odd product/topic with no defineable market.
* Over 50% of all books published never earn back their advance.
* Publishers want authors to earn back their advance within the first 18 months.
* Publishers have to pay extra to put your book on an endcap at the bookstores. They must feel that your book is worth it.
* If you hold out for a higher advance, that money could come out of the marketing budget for your book.
* The high advances paid to top authors do not have an impact on a new author's advance.
* Most publisher's don't break even until your book has sold 7,500-8,000 copies.
* Even if you sell a lot of books yourself, it does not register on the sales count for your book. The only sales they count are those that come through bookstores.