fridge parts
Q: Why do the ice cubes in my frost‐free freezer disappear?
A: Cover them and they will last!
Frost‐free refrigerators draw moist air back to a part that is called an evaporator, which is a very cold metal plate. This moist air becomes ice and the ice will melt from the cold plate when the refrigerator goes into what is called a defrost cycle. The water will flow into an evaporation tray outside the cabinet usually on top of the hot compressor.

Therefore uncovered moist objects including food and ice cubes will be drawn to this cold plate and eventually disappear.