Liability shift
The card networks' rule for who eats a fraud loss: whichever party chose the weaker technology.
It is a carrot dressed up as a stick. To get chip cards adopted, the networks made liability for counterfeit fraud land on whoever hadn't upgraded. If the bank issued a chip card but the shop only swiped the stripe, the shop paid, and vice versa. Europe moved in the mid-2000s, the UK made Chip and PIN mandatory in 2006, and the US followed on 1 October 2015, with petrol pumps granted several more years of grace.
Online, 3-D Secure plays the same role. A purchase authenticated by the issuer moves liability for fraud chargebacks from the merchant to the card issuer. The protection covers fraud only. A customer claiming the parcel never arrived is not covered, which is why friendly fraud still lands on the merchant.