Dash forced tips, but awful service

Why force us to give tips to the Woolies Dash driver when they can't even deliver the parcel to my door, but rather leave it at reception and complain that they have a million other orders to deliver and don't have time to waste? Why are tips not discretionary, depending on the service received? We already pay a delivery fee so I don't understand why tips are forced. What is your policy regarding deliveries at apartments? Are the drivers supposed to dump the orders at reception and hope for me to go get it? If the order is not complete, who will be held liable? Half the time half the items are not even available.