Why does cast iron rust? Without the protective layer of carbonized oil called seasoning, cast iron is susceptible to rust. Even a well-seasoned pan can rust if it's left in the sink to soak, if put in the dishwasher, allowed to air dry or stored in a moisture-prone environment.
If cast iron is cared for properly, it will last a life-time.
Clean the item immediately after use by wiping with a paper towel or clean cloth. If you use water to clean, you are advised to thoroughly dry after every use. Do not use a scouring pad or soap, as this could cause rust spots to develop.
If recommendations to care for your item are not followed, unfortunately it is at risk of rust.