How open are you to the suggestions made by the beta readers of your book? How much of their input are you willing to accommodate in your rewriting process? How do you thank them and make them feel special when their ideas become part of your idea?
The beta readers are usually your family and friends and they are also the worst readers you can get. They already have an opinion (good or bad) about you and they will judge the book through the filter of their feelings towards you. The worst beta readers.
What you need is people that know nothing about you; outsiders which will judge your book solely on the merit of your talent. Of course, their opinion will hurt and you’ll reject from the start everything they say. After you cool down, you’ll find those ideas that can improve your book and use them.
How do you thank those that help you? You send them an email explaining how they improved your book? Do you include them in the special mentions in the book?
One of the most efficient forms of marketing is word-of-mouth (evangelism marketing). Can you determine your beta readers to believe so strongly in your book as they will freely try to convince others to buy it and read it?
I ask because I think enchanting the beta readers is the seed for your book’s success. People will feel strongly about something that is somehow theirs. A beta reader will have a sense of ownership regarding your book. It might be the strongest motivation you could find for him to talk about your book.