When enabled, this makes the device automatically create an RMON Ethernet history collection entry for a port the moment that port comes operationally up, rather than requiring an admin to manually provision RMON history per port. This matters most on devices with frequently changing port counts, such as hot-swappable modules or dynamically provisioned circuits, since it saves an admin from having to manually add an RMON history entry every time a new port is brought into service. For example, on a chassis where line cards are added or ports are activated regularly for new customer circuits, enabling this means every newly-activated port immediately starts collecting Ethernet history statistics without a separate provisioning step.