Most of the time it's because the institutions didn't do their homework before they asked for a permission not to disclose.
The duty to assist is very important. When somebody is asking for an enormous number of files, it's not because there are a lot of documents that the request itself is unreasonable. Sometimes the institution doesn't go back to the requester to try to scope it down and explain to them that they're going to receive 22 million pages. What we often tell the institutions is to start with the duty to assist and talk to the requester to make sure they've done those steps first, and then come to us.
I think that's a learning step. The ones we agree to give are because the requests were clearly made in bad faith. Somebody had already received all the documents and asked for them again—things like that.