This counter is the running lifetime total, in the TotalStatsBin, of IGMP join or leave messages the switch discarded because they arrived on a port without an established router port to relay them to -- the same host-discard condition tracked at interval granularity elsewhere in this MIB, but accumulated here without interval boundaries. Because it never resets on an interval rollover, a large but flat value tells you the underlying misconfiguration was likely fixed long ago, whereas a value still actively climbing means it's an ongoing, current problem. For example, a total that reads exactly 500 and hasn't moved across the last several polls suggests a router-port issue that was already corrected, while a total climbing by dozens per hour means it's still happening today.