Fuel reconciliation is a paperwork exercise in most operations, and paperwork exercises produce discrepancies. Somebody keys a vehicle or tank reference, sometimes correctly, and the difference between what was dispensed and what was recorded accumulates until an audit finds it.
An NFC tag on the tank removes the keying step. The tank identifies itself to the dispensing system, authorisation is checked against the actual vessel, and the dispensing event is recorded with the identity attached rather than transcribed.
The result is that reconciliation becomes a query rather than an investigation, and unauthorised dispensing becomes difficult rather than merely against policy.