There is a fundamental difference between production monitoring and production reporting. Reporting tells you what happened. Monitoring tells you what is happening — and creates the opportunity to act before the situation gets worse.
Most manufacturing businesses are doing reporting and calling it monitoring. A shift supervisor walks the floor at 10am and estimates output. An OEE figure is calculated at end of shift from manually compiled data that may reflect what the supervisor remembered rather than what the machine actually did. A downtime event is attributed to a reason that the maintenance team discussed afterward — not recorded by the operator at the moment it happened.
These are not edge cases. They are the daily operational texture of manufacturing businesses running without real-time production monitoring.