As you could anticipate, it is a basic part of the publishing approach: a book cannot be posted if it does not have a book cover. Most likely much more importantly, it typically is not going to be able to attract viewers if it does not have a superb book https://whitemagicstudios.co.uk/blog/5-things-marketing-consultants-focus-on-when-you-self-publish-on-amazon-uk/