While researching data for a book about personal finance, I came across a website that listed free eBooks. Seven were listed under the financial category, so I downloaded them all and then set about reading them.
They were awful.
Not just bad - awful.
Absolutely pitiful drivel.
"What on earth," you might ask, "could have been so bad about them?"
After recovering from the first reading and reminding myself that "this too shall pass," I took another look at them and decided that while the author/publisher had made many mistakes, the most glaring mistake was that they didn't provide any unique content.
After reading each book, the meat of which was only two pages long, (the rest was advertising for other free ebooks, websites, and memberships), I didn't have any new knowledge that I didn't have beforehand.
"But...does that mean that every ebook I publish should have new information?"
Think about it this way. Let's say that you're a woodworking expert and you publish a book on building clocks. Your prospective customer walks into a bookstore and sees your book on the shelf. As she thumbs through it, she says to herself, "Hrm, nothing new in this book that I didn't already know."
Do you think you're going to make the sale? If there is nothing new in your book that your prospective customers do not already know, what compelling reason do they have to purchase your product?
When you're editing your book, take a few minutes to make a list of all the things that your prospective reader should expect to get out of reading your book. If you cannot list anything new that the reader would not have known before reading your book, take a hard look at your book. Without providing new information, you can't expect your book to last long in the market.