A chargeback is a card payment unwound after the fact: the cardholder disputes, the network claws the money back from the merchant, and the merchant proves the sale was real or eats it. The window runs months; the burden sits with the seller; friendly fraud is a cost of doing business.
Crypto payments invert the default: settlement is final, and reversal requires the recipient to send it back. The merchant's exposure collapses from a months-long dispute window to the wait for confirmations. The buyer loses a protection, which is why good checkouts offer both rails and let the two audiences sort themselves.
U.CASH checkouts offer cards (with their familiar protections, through the merchant's own processor) beside crypto and bank rails (with their finality): the buyer picks the trade-offs, the merchant sees which rail paid every order.
Every term behind the rails, the assets, and the settlement.