This counter tracks packets dropped because they didn't match any entry in the router's route table and therefore couldn't be forwarded. This is the go-to counter for diagnosing 'traffic reaches the router but never gets anywhere' complaints, since it isolates missing or misconfigured static routes as the cause rather than RF signal quality or Ethernet-layer issues. After adding a new remote subnet behind the Endstation port, forgetting to add the corresponding static route would show up immediately as this counter climbing for every packet destined to that new subnet.