This counter tracks BLANK CHECK SCSI SENSE key errors on this LUN/flow, an error class traditionally associated with sequential-access media (like tape) attempting to read past written data or encountering an unexpected blank area. An admin seeing this on a flow to a tape-backed virtual LUN or backup target should suspect a backup job attempting to read beyond the actual written data on the media, rather than a disk-array hardware issue. This error appearing on a flow tied to a virtual tape library backup job would point the admin toward checking that specific backup job's media handling rather than the array's disk hardware.