If cared for properly, non-stick griddles can last for years without their cooking surface eroding. However, when damaged, ceramic, Teflon, and other nonstick pans can begin to degrade. Throw away your nonstick pan when you begin to see flaking or peeling on the cooking surface. Cast iron pans are a bit different and usually won’t peel in the same way a Teflon pan will. Instead, damage to their layer of seasoning will ultimately result in rust. To keep them protected, make sure to reapply layers of oil every two or three months.