1. You wrote an unnecessary book: If there are already 20 nonfiction titles on your subject, does the world really need a 21st? Write a book people will want to read.
2. You have a bad book cover: It is categorically impossible to overstate the importance of a good cover. Hire a graphic design pro or, ideally, a full-time cover designer.
3. Your title is lame: Weak, nondescript, confusing, boring or bizarre titles can hobble a book's chances. If you're just not creative in terms of titles, hire someone who is, like a professional copywriter.
4. You didn't hire an editor and proofreader: I don't care how sure you are that your book is as clean as a whistle, a good editor and a good proofreader will find lots of errors you missed and will offer tons of constructive suggestions that never occurred to you.
5. You think small (part one): If your goal is commercial success, while you need to think big, you need to be smart about it and craft a campaign that effectively reaches your target audience.
6. You promote the old-fashioned way: Forget about the mainstream media market. Identify your target audience, figure out where they hang out online, contact the gatekeepers of those sites and work hard to land reviews, blurbs, interviews, green lights to write articles, etc. And then repeat. Over and over again.
7. You think small (part two): You're not going to make your book a commercial success by sending out a few dozen copies for reviews, publicity and promotion. You need to think big numbers: 350-400 and up. Send them out with carefully crafted materials to an intelligently targeted list, follow up diligently and something's gonna happen.
8. You forgot that you have just ONE job: As a self publisher you have one job: Build demand for your book.

The above list is an abbreviated version of an article by Peter Bowerman. For the complete article, go to: http://EzineArticles.com/?expertPeter_Bowerman

For more about Bowerman and his work, go to: http://www.wellfedsp.com