My experience with Amazon delivery guys is they look completely lost, and I don't think it is their fault. They are nice, nicer than postmen and deliverymen from well established companies like UPS, but as soon as something unexpected happen (if you can call "not at home" unexpected) things become complicated.

I often get "I don't know", "I need to call my boss", "this is not my route", etc... They don't have the master key for my mailbox or entry hall, they don't have a drop off point where I can pick the package later, I can't even go to the warehouse and pick my package there, tracking events are inaccurate, times are highly irregular ... None of that happen with other delivery companies.

They really look like amateurs doing their best with limited means, it is difficult to imagine they are backed by one of the biggest and most technologically advanced companies in the world.