Low Forward Voltage Can Support LED Wear-Out When Physical Damage Is Absent

What the evidence preview establishes

Premature device wear-out was the most likely explanation for the luminosity degradation. The failed LEDs had depressed forward voltage without a repeated physical signature of EOS, ESD, construction, or workmanship damage, consistent with degradation within the active region rather than a gross interconnect failure.

Why this case matters

An LED can lose output through active-region wear-out without displaying dramatic physical damage. Compare forward voltage at the specified current, include a good control, and resist elevating isolated microscopic anomalies above the repeated electrical pattern and the absence of a common overstress signature.