There is a lot of experimentation and testing involved in all stages of publishing and also writing process. As for the price, however, I don’t think it would make much sense for someone who has never been published before and is completely unknown as an author to push the price high when trying to attract the readers.
Also, how about those who cannot afford a higher price? Since I myself ended on welfare, I understand those people all too well and I also understand how being on welfare says nothing about who you are, how smart, competent or deserving you are. After all, J.K. Rowling was on welfare, what did that tell anyone about her? I want those less fortunate to be able to afford my book, and that’s one of the reasons why I went for the lowest price on Amazon.