While they may seem similar at first, Shelves and Lists serve different purposes on Blackauthored.
Shelves help you better organize and track your reading progress beyond the basic statuses. For instance, you might have a shelf named “My 6 Star Reads.”
Lists, on the other hand, are meant for curating and sharing collections of books around a theme, topic, mood, or idea (e.g., MMCs who are down BAD).
In short:
Shelves = personal organization & reading tracking
Lists = curated collections & recommendations