This read-only Counter64 counts the number of times this PM instance timed out waiting for the router to send its next query. A growing count is an early warning that the upstream multicast querier has gone silent or died, which — left unresolved — eventually ages out all group membership on the port; because it is drawn from this instance's running statistics bin, it behaves like a long-running total rather than a rotating window, so admins baseline against it instead of expecting it to reset daily. On an access port serving a multi-dwelling unit, a count of 2,772 over the current statistics window is the kind of number an admin would trend against the join/leave rate on the same port to judge whether it's normal channel-surfing or an anomaly worth a closer look.