An invoice agent hits a transient timeout, retries, and two payments clear to the same vendor. The model calls it success. Ops calls it a week of cleanup. Spend limits and roles are a speed bump. Real delegated authority is a delegation object, policy on every attempt, ledger-bound idempotency, and an instant kill switch.
A payroll rollout taught me the friction is never the integration. It is funding caps, routing permissions, and what can clear directly versus what has to detour through a sponsor bank. That is why the Fed's new payment-account RFI matters - access is becoming a design decision, not just a policy one.
From March 2026, Nacha standardizes the ACH Company Entry Description as PAYROLL or PURCHASE for those payment types. It sounds trivial, but a free-text field becoming a dependable category is what finally lets reconciliation automation stick on a rail that still moves tens of billions of payments a year.
FedNow matched RTP at a $10M network limit in November 2025 and added new risk rails - a receiver-account pre-check pilot, ScamClassifier reporting, an Exception Resolution Service, and 1,500+ banks live. Instant is treasury cash now, and batch-era controls just got a 24/7 bypass.
Your bank says it is "ISO 20022 ready" for the November 22 cutover. Check the docs and it is usually a translation layer - MT to MX at the SWIFT boundary, MX back to MT inside. That is compliant, and it quietly throws away the structured data that was the whole point.
The CFO sees "save 3 percent on transactions" and the math looks obvious. Treasury sees continuous settlement at 3 AM and a reconciliation process built for batch. Before you switch to account-to-account, count the operating cost the savings slide leaves out.