In the self-publishing process you want total control from start to finish. You want to make the decisions, not Mr. Big Publishing House, Inc. You want to own all rights and have complete control of your book. By maintaining control over the editing and proofreading process, you have the ultimate say with what actually stays in and what is omitted. You are again “in control” of what the audience reads as the final printed version. With big publishing houses or publishing companies, they often will want to edit and omit parts of the book you actually want to leave in. These publishing firms sometime delete too much of the important parts out of your introduction or parts of chapters that you think or know will be important to your book.
You want to remain in control over your work. You want to keep control of the entire writing, printing, & selling process. Bottom line is you have 100% control when you self publish.