I opted to just let him continue his normal routine. Undoubtedly faster than doing a one-off signature because I happened to be standing out in front of my house.
For a while, my home had very poor labeling of its address on the building, and getting anything delivered was always a crapshoot of drivers giving up and just picking a random location to leave it instead. They would happily take photos of them having left it at a home that was not mine, not remotely mistakable for mine, and Amazon didn't treat that any differently from the cases where there were no photos at all.
My guess is one of two things, either Amazon contracts out overflow work, or some of the contracting companies have high employment standards and some don't.
I've had my packaged signed for by "mailbox". This is practically the default message for me.
I've been on vacation and seen "Handed directly to a resident". Which would be more disturbing if I didn't already know the whole system was broken. In this case, the package was sitting on the front steps.
(Edit: These are all Amazon branded van deliveries, fwiw).
I tried to help an Amazon driver by taking the package from him at the edge of my driveway. He stopped me, told me he had to take a photo of it sitting on my property first. He was very serious about this. I highly doubt this behavior is from these contracted drivers unless the photo requirement is new and your experience is not.