Given the background description of some cooking related query, summarize the question into a title

Q: Every recipe about searing duck breasts I've seen says that you should score the breasts cutting through the skin, but not too deep: you should avoid cutting into the meat. I do follow this instruction but don't completely understand why. What harm could be done if I cut through the meat, just a little? What exactly should I avoid?

A: Why not to cut into the meat when scoring duck breasts?
****
Q: I was wondering what taste good as a filling for chicken breast. I want to make kind of chicken breast pockets by almost cutting through the chicken breast but keeping both sides still together to fill. Then I will fill it and close it with some string or tooth picks. That's very much for any suggestions!

A: Filling for Stuffed Chicken Breast
****
Q: I have a problem. Let's say I buy a frying pan for about 130 EUR. But after 5 months of using it 3 times a week, it looks like the photo. What am I doing wrong please ? (I never scratch the pan. I always wait until it's cold before washing it, I protect the Teflon with shoam)Edited: to react to your comments, my habits are: preheat the pan for about 6 minutes on the biggest flame without oil - to prepare it for a steak. But i use it like this for about 20% of time. Is preheating damaging the Teflon? If so.. what material should i use?

A:
Frying pan Teflon damage
****