DLRs are requested on a per-message basis. If you do not request a DLR, you will not have a record of the result of the transaction.
A Delivery Receipt (DLR) is an acknowledgement from a destination carrier network that a message was successfully accepted or rejected (and the reason the message was rejected). TSG Global supports DLRs on SMS and MMS if a customer has their requested delivery status flag set appropriately. The DLRs will be delivered to your inbound webhook/URI if requested.