It's common for dogs to prefer to go indoors, particularly for #2 - it's a vulnerable position, and they often prefer a nice, quiet spot with some comfy carpet to squat on.
Thor just marked the wall next to the potty pad.
He was definitely aiming for the wall and not the pad, because he squatted on the pad just a few minutes ago. We were doing so well! Do I have to re-start the count? This will be our ninth day if we keep going. Sometimes I think Thor is actually a genius and enjoys toying with me.