I have found that what many people think is stuck on and must be scoured will come right out if you let hot water sit in the pan for a few minutes - Very similar to other's comments about boiling water in the pan.
As I start my workday, 03:00, I sit with my laptop, in my recliner, with coffee, and old westerns or cop shows on. They run adds for the latest and greatest non-stick frying pan. Lately it has been some fake copper thing with a non-stick coating. They brag that it is safe in the oven up to 500f. Ovens go up to, and some over, 500f. How hot do you think a frying pan gets sitting on a burner searing meat or frying potatoes?