Having recently tried to use some OER in anger, we download a QuestionMark questionset from a well known repository. On installing the qpack, we noticed that there where questions with graphics missing. There was a name and an e-mail next to the releaser, so I thought may as well drop them a line to see if they had the graphics handy. The releaser it seems was not the releaser of the materials but the author of the questionset. So someone else had released the materials without giving it a proper review. The releaser was very helpful though in getting the images to us, but as they mentioned they are under extreme pressure in the normal work instances.
A lot of people might not be aware of the extra workload and communication involved in OER and really should. Someone might get in touch and expect an answer, others might be after more information about a specific subject. Quality control is something that needs to be rigourus especially when releasing materials out into the wild and people need to be aware of the possible extra time after publication.