If you don’t know what the central, golden nugget is in your book, if you haven't distilled it to that one central tenet, you'll fail to find your book's marketing message. Marketing your book becomes easier when you can zoom in on what makes you and your book special.
Every one of your readers has his or her own preferred way of learning a new thing. If you don’t account for these disparate learning methods within your blog post or business book, you’ll be turning a chunk of readers off without even realizing it. Each of us has our own personal bias when it comes to learning, which can lead you astray when it comes to writing for a broad audience.