Double doors in case you have to move something big (like furniture and desks and stuff) through them?

This seems to be the common suggestion, but since the corridor outside isn't as wide as the doors, I think any big furniture would have to be broken down to get to the room in the first place, so that doesn't seem likely to me.

Perhaps double doors were just needed for the symmetry of the room? In any case, they are good for anything which is a bit bigger than single door size, but still small enough to fit in the corridor.