Normally they monitor conditions defined by the appliance design, not the centre of every stored item. The display's meaning must be checked in the model instructions.
What the observation tells you
Large and small packages respond differently to a temperature change. A target or cabinet reading therefore cannot reconstruct each food's complete history. This matters particularly after loading or an outage when food and air may be at different stages.
A useful next step
Use the appliance information for operating assessment and official guidance for food decisions. Do not puncture packaging or dismantle sensors to create a comparison for a repair enquiry.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.