This counter reports how many MAC addresses have been removed (aged out or cleared) from the device since MAC Information was enabled globally and on at least one interface. Comparing it against hh3cMACInformationLearntMACNum lets an admin gauge MAC table churn, such as unstable end devices or misbehaving switches flapping in and out; it also resets to 0 whenever the feature is globally disabled. For example, a rapidly climbing removed count alongside a steady learnt count could point to a device on the network that keeps reconnecting with a new source port.