 mistakes you're making with your stainless steel pan. Cooking sprays tend to have emulsifiers, propellants, and anti-foaming agents that build up a sticky coating on your pan. The thermal shock from the change in temperature can literally warp the metal. This will be even worse if the pan was overheated, which is also a thing. Heat your pan on medium-low heat for one to two minutes. When it's ready, a bead of water should float around like a marble. If it's too cold, the water will evaporate quickly. If it's too hot, the water will separate into droplets and dance around the pan.