This counter tracks the number of cells received on the Virtual Channel Link that were deliberately dropped by the switch due to traffic-policing violations, meaning the traffic exceeded its rate limit or exceeded allocated resources. Network engineers use this to detect whether traffic is violating its service contract and to adjust policing rules or customer bandwidth allocations. If a customer's VCL shows 50,000 discarded cells per hour but they're only paying for a 1 Mbps circuit, it's clear they're attempting to send unauthorized traffic and need to be throttled more aggressively.