This counter tracks the number of POLL PDUs transmitted on this port, per the description, sent by SSCOP to solicit a STAT status report from the far end, triggered by either the MaxPD PDU-count threshold or the TPoll timer. This rate is a direct function of how those two settings are tuned relative to actual signaling volume on this port, so an unexpectedly high count here (relative to actual SD PDU traffic) suggests TPoll may be set more aggressively than the link's traffic pattern warrants. Comparing this against NumStatPduRx confirms whether polls are actually being answered.