Why do eggs stick to frying pans, no matter what material the pan is made of?

After prior use, the pan might be insufficiently cleaned, causing the eggs to stick, resulting in an inadequate layer of food residue. Not all non-stick pans are equal. Some non-adhesive panels that are ceramic coated or copper do not work, and some teflon panels still require a little fat/oil to not be adhesive. Cooking and pre-heating food at the appropriate temperature is somewhat required in order to optimize the non-stretching property of the cupboard.