Counts routing table entries discarded even though they were still valid, with the DESCRIPTION noting this is typically done to free buffer space for other routing entries. This is a route-table churn indicator distinct from the traffic counters elsewhere in the MIB; a rising value suggests the device's routing table is under memory pressure and is evicting valid routes, which can cause intermittent reachability loss to destinations whose routes got prematurely discarded. Example: ipRoutingDiscards climbing after a large batch of dynamic routes was learned from a newly peered network suggests the routing table size is now bumping against a memory ceiling on that gateway.