Element #5 of a book that is ready for self‑publishing:
[ Images and quotes are accurately credited, licensed, or cited ]
This means that quoted material used in epigraphs and throughout your book have been researched for accuracy.
For nonfiction titles, sources are cited either in text or at the back of the book.
Images are either public domain or personally captured, or applicable licenses and permissions for their use have been acquired.
Images are credited accurately.
Two sites that I visit regularly for public domain images for my blog are pixabay and morguefile.
What are some characteristics of a book that isn’t ready?
Quotations are attributed to the wrong person or unattributed, or repeated incorrectly, and images are used without the appropriate license or permission or are not credited properly.
Repeating quotes incorrectly might cause an author to merely look sloppy or might go unnoticed. But publishing images without permission and citing sources incorrectly leaves an author vulnerable to lawsuits.