[mothered]

How will the delivery driver proof that they actually dropped off the product? They could have stolen it.

They're not dropping It off, but rather waiting for a member of the household to accept It after they knock on the door:

its teams will place the parcel at your door. Having knocked on the door, the delivery teams will step aside to a safe distance while the item is retrieved.

The operative words are:
while the item Is retrieved

Meaning they'll await for a household member to personally accept It and If they neglect to do so, the delivery Is redirected to a local collection depot.