SMART
SMART health metrics that actually move decisions
Stop memorizing hex IDs — learn which curves predict action.
Reallocated sectors (grown defect pool)
Slow upward drift can be manufacturing variance; rapid acceleration suggests surface trouble — prioritize cloning.
Pending sectors
Often precede permanent realloc events — treat instability clusters seriously even when totals look small.
Interface CRC / communication errors
Rising counts frequently trace to cables, docks, or USB bridges — fix link quality before blaming platters.
Power-on hours vs workload
Aging alone does not doom drives; duty cycle plus thermal history matters. Pair POH with peak temperature logs.