Something I've taken more notice of recently, couriers request 'authorisation to leave' shortly after they pickup the delivery from the supplier. 

I just received a text from DHL asking for this. 

The fine print of these requests includes ...

"I release DHL and my shipper from all liability for loss or damage that may result from delivering the shipment according to my request"

Shippers must love it when people tick this box. I would never give this authorisation. 

Just the other day, a neighbour came over with a package for me that went missing nearly a year ago. Courier had neatly hidden this small item inside their garage. At the time, courier was adamant they delivered it because GPS showed their van outside my house at the delivery time.   Probably should not have self signed it !