They're both # 1 in the series and will definitely lead to a lot of sales of the other books in the series. (dealsagar.com)
While they may initially lose out on some royalties for that particular title, the expected sales of the other books in the series could very well make up the difference and then some. (goodereader.com)
How can an author compete with the hundreds of thousands of other books on the market? (unrulyguides.com)