When we had our porch built we deliberately chose to have clear glass in the door. That way the front door gets opened, but the porch door is kept locked until we know who the caller is.
There are times when we ignore the doorbell completely, when we've heard delivery men knocking at our next door neighbours house. We must have taken upwards of sixty parcels in for them over a period of less than a year, but not once did they ever thank us for doing so. The straw that finally broke this camel's back was on a glorious day in spring of this year, I was weeding at the bottom of our (very long) garden, our doorbell rang, I dashed to the door only to find it was yet another parcel for the neighbours. I took it in, and before I returned to the garden went upstairs to open the dormer window wider........and saw 'her next door' lying on a lounger in her back garden! I thought perhaps she hadn't heard her doorbell/knocker, but when I took the parcel to her later on my way out shopping, she said "Oh, that's what the knocking at my door must have been, I was sunbathing and couldn't be bothered getting up"!
They're a young couple, he's 33, she's 32, he works, obviously is on a good salary because she spends a huge amount on clothes, which she has delivered!
Since the 'sunbathing' episode, if she doesn't answer her door, she doesn't get her parcel!
Yeah, I'm a grumpy old woman, and proud of it!