"Print on demand" technologies, which allow it to be doable to print as few as one particular book at a time, have made self-publishing (and Vainness publishing) easier and more affordable, and it has authorized publishers to keep minimal-selling books in print fairly than declaring them out of print. https://robustdirectory.com/listings1272014/the-smart-trick-of-barnes-and-noble-coloring-books-that-nobody-is-discussing