Self-publishing has some obvious perks:
Freedom to publish whatever you want whenever you want
Artistic control over the length, layout, and cover of your book
Immediate income for each book you sell
Some flexibility in the book pricing
Not so obvious are the draw-backs. As the sole producer of your book, you have more freedom and control but also more responsibilities such as:
Researching book-buying markets to see if your book fills a need
Writing and revising your manuscript without editorial feedback or assistance
Correcting mistakes in grammar, spelling, and syntax
Typesetting your manuscript to provide the printer with camera-ready copy
Applying for an ISBN Number and paying fees required to copyright the book
Locating artwork to illustrate the book's content and cover
Paying for the artwork
Deciding on quality of paper, font style/size, type of cover
Deciding on the press run and paying the printing costs
Marketing the book
Promoting the book
Requesting book reviews
Trying to interest newspapers, magazines, and talk shows in interviewing you
Promoting the book
Promoting the book....
If you have a super-hot topic that has not been addressed, your book might generate interest fairly quickly. Since this seldom happens, you might be stuck with boxes of books that you paid to have printed.
By contrast a traditional publisher handles all of the above responsibilities with the exception of researching and writing the book. If the book does not do well, the publisher bears those costs, not you. If you receive an advance, you do not have to pay that back unless you fail to complete the book as promised.
A traditional publisher takes on the time and expense of editing, proofing, printing, and marketing your book. Therefore, you can be sure the company will put forth professional efforts to be sure you have a lively, interesting, well-written manuscript that readers will be eager to buy.
If, however, you have a ready market waiting for your work or you decide to go ahead and self-publish, please get a professional critique before you typeset your material. I've been critiquing poems and manuscripts for 30 years and will be glad to work with you - for a reasonable fee, of course:)
(c) 2009, Mary Harwell Sayler