What should authors know before they publish a book?

[susanstorm]

I’ve been thinking about how to publish a book, and I’m realizing there are more decisions than I expected. How do first-time authors decide which format, editing level, and publishing route fits their goals? What should someone check before signing an agreement, especially regarding rights, revisions, distribution, and future editions? I’d appreciate honest experiences about mistakes you made and what you wish you had known earlier.