I agree with what Carl said. The interior was painted before the exterior.
The seat frame skirts on my truck had orange overspray over the beige interior color. Just a few spots that were barely visible, but definitely orange.
The masking job around the doors doesn't need to be perfect though, as the weatherstrip covers the corner where the door skin folds over the door interior, and would cover a bit of masking the wasn't exactly on the edge of the door skin fold.