This read-only counter, in cells, tracks the number of valid OAM cells in the egress direction of this channel discarded at the class-of-service queue. An admin cares because losing OAM cells on the way out can prevent the far end from receiving expected fault-management signals, potentially masking or delaying detection of problems on this connection. For example, if a remote endpoint reports missing continuity-check cells while this discard counter is climbing, the admin can attribute the missing OAM traffic to local egress congestion rather than a remote-end fault.