five minutes is a unit of measurement that has, over the long course of a domestic life, become detached from clocks. it means: long enough to have walked somewhere with a reason, short enough that you should not, on returning, be inconvenienced.
the note was left at quarter to twelve. it was found at half past one by someone who had a small parcel and no patience, and the parcel was left on the step. by the time K. returned the rain had begun, and the parcel had taken in a slow, papery hour of it. the meter man came on the wednesday and asked about the catch on the door.