This read-only Counter tallies the number of frames discarded on egress specifically because the egress queue depth was exceeded, reflecting the hard-drop behavior configured via egressQDepth; it is not supported on FRSM12. An administrator watches this to confirm egress buffer overflow, specifically, is causing loss on a channel rather than a physical-layer or CRC-related problem. For example, a rising xmtFramesDiscXceedQDepth on a channel whose egressQDepth was recently lowered would confirm the tighter threshold is now being reached by real outbound traffic.