I have recently come across two cases of an author asking for their paper to be withdrawn from the proceedings (online, OA) of a conference.
I am pursing these cases as I can to find out why. I assume that the conferences did not have an appropriate license agreement allowing them to make the paper OA, though few authors would pay much attention to that anyway. There are a variety of possible reasons; perhaps reader of this list can suggest others: 1. The authors want to publish their paper in a journal as well to get double counted value in their cv from their research. 2. Conferences don't count for anything in their field, but journal articles do. 3. As above in 1 and 2, and the authors have been scared by publisher's words about `prior publication' invalidating submission. 4. The work is plagiarized, fraudulent, or is a case of multiple papers spread over one research nugget, and the authors do not want to be found out. 5. The authors do not believe the Internet is suitable for scientific publication and discovery. 6. The authors are in their 60s or 70s and set in their ways (not Internet-savvy). ... It is worthwhile trying to understand these counter-intuitive actions. There may be lessons to be learnt. Arthur Sale University of Tasmania