So think, if you have your own awesome ebook selling beside a not so awesome ebook of another that offers another 1 or more ebooks if bought, which do you think would be more appealing? One of the main reasons is providing a bonus or lower cost. There are different ways of providing discount rates. One individual might provide 10% lower cost to the first 50 buyers and another individual might provide a 50% lower cost on their second e-book if customers buy the first one at regular cost. But discount rates help! Most people browsing over the internet for buying e-books are looking for lower cost - it is more emotional than cost driven. So the concept here is to provide discount rates and rewards.