Nobody talking about the refrigerators in Europe. They work differently. The ice forms inside the fridge part not just the freezer part. I don't know why and have not looked into it but it is in every fridge, including brand new ones.
Ice forming inside of the fridge is a result of moisture making its way into the fridge and staying in contact with the cooling elements.
The cause can be a lot of things, from broken drain pipes to damaged door seals. A well-functioning fridge shouldn't have (much) ice buildup unless you live in a hot and humid area.
Some modern fridges (usually the luxury models) also have features to defrost themselves if they detect that there may be frost buildup, but many fridges still have you do it manually.
