UV fluorescence testing helps reveal early stage module degradation that may not appear in performance monitoring or visual inspection. Customers should care because issues such as moisture intrusion, encapsulant degradation, and seal integrity failures can silently reduce long term reliability and may eventually lead to underperformance or premature failure. UVF testing provides objective documentation that supports maintenance planning, warranty evaluation, and insurance discussions, especially when the goal is to understand long term module health rather than only identifying current electrical failures.