When normal people knock on my door, in a normal way, my dogs do as they've been trained to do and go to their beds.
When the lovely lady from Hermes knocks on my door in a nice, normal way, the dogs go to their beds.
When my Dad knocks on my door, the dogs sense it is him and wait patiently in the hall until I let him upon which they dive at him with gusto.
When Royal Mail knock on my door in the way at only Royal Mail do, I jump so far out my seat I almost hit ceiling, Whippy runs terrified into her crate and Devil Dog decides he must protect the house from the person trying to break down the front door at all costs, including snapping at me when I restrain him to get him into a different room, before they attempt to kick the door in again knock again, which they inevitably do.
I would complain but I have a feeling bad things might start happening to my mail but it is really necessary for them to knock so loud it would wake the dead? Really?! I can't be the only person who has problems with Royal Mail couriers scaring them half to death?