A non-custodial service moves value without ever holding it: the platform routes, matches, and notifies, but the keys, and therefore the funds, stay with the owner. Every settlement lands at an address the user controls, and every action is a signature the user gives.
Custody is the difference between a bank and a rail. A custodial wallet is an IOU; a non-custodial one is the asset itself. The trade-offs are real (lost keys are lost funds), but for a merchant the question is simpler: can the platform run away with the till? Non-custodial means it cannot.
Non-custodial is the whole architecture: swaps settle to your wallet, checkouts settle to your address, U.CASH never holds a merchant's or a buyer's funds at any point in any flow.
Every term behind the rails, the assets, and the settlement.