A freezer with a mid-range build quality has an anti-ice buildup function: Low Frost or No Frost. The freezer will have little to no ice formation. As a result, the compressor can cool your fridge with minimal power, which improves the life of the engine. Unlike a top-notch freezer, a mid-range model usually has a conventional compressor, not an inverter. This compressor doesn't work constantly, but intermittently. Because it's constantly turning on, it wears down where an inverter compressor doesn't.