It looks like you are sliding your pans on the burners, which is a no-no with a glass top stove. What are you using to clean it? Get some of this if you don't have it: Cerama bryte I like the creme rather than the spray. Use a scrubby sponge (nylon only, no metal) then wipe with a damp cloth, then wipe dry with a towel or paper towel. I have better luck with the creme than sprays and I've never had good luck with any of the Weiman products. You should clean it every time you cook if anything ends up on the cooktop, splashes or splatters, especially grease. Don't use cast iron unless you are really careful to not slide it at all, as it will scratch the surface. Make sure the burners are completely cool before cleaning and if you get stuck on food, use a straight edge razor at an angle to scrape it off. You tube has videos on how to clean and use the razor blade on a glass stove. Good luck!