there is that, also with the front wheel off, if the spacer thingee you must put in so the pads dont get pushed out too much when the brake handle get squeezed, then apparently this can be a problem.
general rough handling of the bike also, depending on your trip type and situations that arise.

mech discs too will have possible disc damage to contend with, and learning the tricks etc of dealing with pad rub and how to avoid that sort of thing.