Two kitchens, two failure patterns
In the older streets the recurring problem is space: a built-in dropped into an alcove sized by eye, cabinetry tight to the case, and a soffit over the grille. Those units run warm in summer for reasons that have nothing to do with refrigeration, and the first readings we take are air temperature and clearance rather than anything internal.
In the newer houses the recurring problem is duty. A wide side-by-side open to a living space gets opened far more often, holds more, and is expected to be silent while doing it. Door seals, hinge cams and evaporator fans wear on that pattern, and they wear predictably.