In banking, real-time is a spectrum. At one end, you have transaction processing — when a customer makes a payment, does the balance update immediately? At the other end, you have reconciliation, reporting, and analytics — when does that transaction show up in the general ledger, the risk dashboard, the regulatory report?
Most banks are real-time at the customer-facing layer and batch behind the scenes. The customer sees their balance update. But the accounting systems won't reflect it until overnight. The risk systems won't see it until tomorrow. The regulatory reports won't capture it until month-end.
This creates problems.