Libby vs Hoopla
Librarian here. If anyone's curious about the difference between Libby and Hoopla, here's a rundown:
Libby - limited selection but better quality and more economical for the library. Libraries pay a publisher for a certain number of digital copies, which expire after a certain number of checkouts. Because of this, they are treated more like physical copies--thus the holds lists. I always check here first.
Hoopla - larger selection but a lot of junk. Not all junk though and there may be some overlap with Libby. Also much more expensive for libraries because they have to pay per checkout rather than per title. No holds lists tho*. I try to use it sparingly. For audiobooks I know I'll want to revisit, I use Libro.fm, which benefits my local bookstore of choice. I don't have anything to do with Amazon anymore (including using GoodReads...try StoryGraph instead).
Addendum: some users have reported waitlists for Hoopla titles. I haven't experienced this in my 10+ years of using it. My guess is that these folks are in very large markets where costs can quickly get out of control if too many people check out the same book at once.