The texture on the upper part of the inside of the door (where your left arm may rest) is like a cheese grater for your skin. I kept leaving my epidermis on the door on my Mazda3 until I discovered Lexol Vinylex. It sort of seals the rough surface and gives it a nice low sheen. I started to notice the same thing on my CX-7 after a week of driving and whipped out the Vinylex. The skin cheese is gone! It's good for about a month before you need to re-apply.