In our publishing classes each quarter, I discuss the commitments a buyer makes versus the commitments a reader makes to you (the author). It's an important distinction because so many of you are choosing to publish your own work, and the behavior of book consumers is the same as it has always been no matter what formats you choose to offer: People buy books for themselves to read. People buy books to give to other people.
While I hear many authors ask virtually anyone in their path to "buy my book;" what most don't recognize, is that there is a much bigger commitment at work. Take a few moments to consider what you are really asking of your consumers; and remember that your buyer and your reader may or may not be the same person.
The commitment from the buyer is simple: You sell me a book, I'll commit $20 for it, and you deliver it to me in any form I want. Done and done.
The commitment from the reader is complicated: I'll commit the time to read it and think about what you say. I may also commit a portion of my self to actually making a change you recommend, or furthering an idea you suggest. In some cases, I may even change my life. You tell me I'll be either entertained, informed or educated and I'll commit the time to see if you deliver.
Make certain that your book does deliver what you promise in your marketing, and be thankful for the valuable commitment your customer has made to you.