once lived in a complex of maisonettes. My neighbour had a small garden with flimsy wooden trellis as a wall. The postie kept on leaving the post outside the gate, in the main passage way. One day, he was caught in the act, and asked why he wasn’t posting the letters through the door. The answer given was that the notice on the gate said beware of the dog. Somewhat flummoxed, my neighbour explained that the printed notice (in a clearly legible large font) said:
Please post letters in the letter box, Thank you.
He also added that they had never owned a dog!
Ho hum….