Sometimes in the rush to get a book to publication, quality can be compromised. It's especially tempting when self- publishing an ebook because downloading the file and clicking that button are just too easy.
Quality Control Check before publishing:
1. A fully-edited manuscript. (And even then, typos just have a sneaky way of slipping through. Grrr to typos!)
2. Formatting. Pay a professional to have it done right, it's worth it!
3. Cover. Your cover design should reflect the tone and genre of your story. Especially with online sales, the cover can make all the difference. It should look professional.
4. Description. I've seen book descriptions with misspelled words, missing punctuation, poor grammar, and I wonder what the book will read like if so many mistakes slip through a brief paragraph or two. The ideal description will make a person want to pay money for the experience of reading the book.
5. Details. Small details can enrich or (unfortunately) ruin the reading experience. Everything from typos and formatting to how chapter headings are designed, how paragraph breaks are done, whether or not the character names are suited to the story, and even comma usage. One or two departures from standard punctuation won't bother me, but when I'm into an ebook several chapters and notice repeated errors (like commas used for semi-colons and semi-colons for commas) it's a huge distraction.
A book must be so well-written, so thoroughly edited, so polished and professional that it really is a wonder when anyone tries to do it alone. Very few of the successful self-publishers do. They hire professionals to help them with all parts of the process to get that quality product readers want.
You want book sales? Don't forget the Q word!