Appliances have a lifespan of 10 – 12 years on average. To ensure proper operation it would be good to regularly check your refrigerator and freezer door gaskets. Not only do they need to seal properly against the unit for efficiency but they also need to remain clean to prevent damage. Sticky substances can cause the gasket to rip.
Also, as a safeguard a thin layer of vaseline or petroleum jelly can be applied to help softern a dried gasket so that it will form a good seal around the door.