Freezer burn is a drying-related quality change and does not, by itself, diagnose a freezer fault. Packaging and storage duration are important parts of the explanation.
What the observation tells you
It should not be confused with evidence that previously thawed food is safe. An item can have more than one storage problem, and its appearance cannot reconstruct its temperature history. A surface patch is not a reliable indicator of a failed thermostat.
A useful next step
Review wrapping and dates, and assess any actual temperature concern separately. Follow food-safety advice for uncertain thawing histories rather than treating the phrase 'freezer burn' as reassurance about every affected item.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.