I lead a book club once (Designing Data Intensive Applications)- read a chapter and meet every two weeks. Was a real flop. Attendance remained high, but only one other person actually finished the book.
What was a real slap in the face - maybe a year after that book had concluded, someone told me I should lead another one about this other topic. She had not finished the first book, and she wanted me to regurgitate another to the group?
Maybe there was value in the discussions that didn’t require the reading? But running seminars isn’t hobby material. If this was happening at my work, I may skim or not even read parts of the book, and still attend discussions.