And we have another thread in the queue asking whether I would answer the door of my home with a gun in my hand after seeing a fedex truck outside.
Of course not.
The situation at hand, being approached at an atm by a stranger, appears to be a moderate threat risk.
A ringing doorbell is way down on the risk scale, but I'll still be assessing risks, just like I do when driving. once further intelligence has been gathered, I'll either answer the door, ignore the door, and possibly kill the guy on the porch because he broke down my door.
This all starts with looking out the door, and asking yourself, "am I in danger?" Not everybody hears the same answer.