No, many AnswerDash customers provide their website visitors and customers with AnswerDash contextual self-service, and they do not have knowledge bases. If you do have a knowledge base, however, you can keep its content synced with AnswerDash.
AnswerDash integrates with Zendesk, Desk.com and Freshdesk, and brings its content forward to visitors in the UI, in context, and in the flow of what they are doing on your website. If you've spent time writing great help center and support content to answer your customers' questions, AnswerDash is a powerful and compelling way to engage more visitors with those answers. You don't need a knowledge base to install and use AnswerDash, as the AnswerDash Q&A that you publish exists independently from knowledge base articles (if you have them). Again, having a knowledge base is not required at all.
AnswerDash simply makes it easy to import information from your knowledge base, so you can pull this information forward in context to visitors on the webpages where they have questions. And you can manage the content in both systems simultaneously, not having to worry about managing content in both systems independently.