This INTEGER, indexed by ifIndex, counts LLDP frames received on that port that contained detectable errors. An admin uses it to distinguish frames that were structurally invalid (this counter) from frames that were valid but simply discarded for other reasons (lldpNeighborFramesDiscarded), narrowing down whether a link has a signal problem or a protocol mismatch. Rising error counts alongside physical-layer errors on the same port would point an admin toward a cabling or interface hardware issue rather than a configuration problem.