Re door knockers - why do people ring the doorbell, then immediately hammer on the door and ring the bell again? I can't materialise at the door instantly when I hear the bell, I have to walk from the kitchen and across the hall, wiping my hands on my apron as I go.
Those who are most insistent in demanding that I appear at once are usually the ones I am least interested in meeting, as well, once I find out what they are there for.
I need an illuminated sign that says "Yes, the bell did ring. If I am at home I will open the door as soon as I reach it. If I am out, I won't hear the bell, and I won't hear you banging on the door either."