Food sticking to a pan is a chemical bond rather than a mechanical accident. Understanding what forms that bond explains why the two standard remedies behave so differently over time.
Sticking is a bond, not friction
Metal surfaces that look smooth are covered in pits at a microscopic scale, and hot proteins flow into those pits and then set, anchoring the food physically.
At the same time, sulphur and other reactive groups in proteins form actual chemical bonds with the metal surface, which is why fish and eggs stick far more aggressively than starches do.
Breaking the food free tears it, because the bond is often stronger than the food itself, which is the familiar result of turning a fillet too early.
Heat and fat govern whether the bond forms
A pan brought properly up to temperature before the food arrives causes the surface of the food to set almost immediately, so less protein has time to flow into the pits.
Fat fills those pits and forms a physical barrier, which is why a thin film spread across a hot surface works better than a larger quantity poured into a cool one.
Moisture works against both, since water on the food surface cools the pan locally and delays the searing that would otherwise prevent contact.
Seasoning is a built-up polymer layer
Iron and carbon steel pans develop a release surface when thin layers of oil are heated past the point where they polymerise into a hard, bonded film.
That film is not oil sitting on the pan; it is a new material chemically attached to the metal, which is why it survives cooking and moderate washing.
It degrades through acid, prolonged simmering and aggressive scouring, all of which strip layers, and it rebuilds with use, which makes it a maintained surface rather than a permanent one.
Synthetic coatings degrade rather than rebuild
Fluoropolymer coatings work by presenting a surface that proteins cannot bond to, which is why they release food with almost no fat at all.
They cannot be repaired. Once the layer is scratched, thinned by high heat, or worn by abrasive cleaning, the exposed metal beneath sticks and the damage spreads outward from that point.
Sustained high heat is the fastest route to failure, which makes these pans a poor match for searing even though they are excellent for eggs and delicate items.
Matching the pan to the task
The practical division follows from the failure modes rather than from any hierarchy of quality between the two surfaces.
High-heat searing, oven transfers and long browning belong on iron or steel, where heat is the mechanism rather than the threat.
Eggs, delicate fish and anything cooked gently belong on a coated surface, used at moderate heat and replaced when it stops working rather than persevered with.