Understand the Anti-Overspray Mechanism

What happens here

The presenter concludes by explaining the effectiveness of this masking technique. When spray painting the window trim, any overspray from the paint gun will hit the inside surface of the secured, folded paper flap. Instead of running directly down the already painted wall, the overspray will be deflected outwards, or 'kick out,' preventing drips, runs, or paint contamination on the adjacent wall surface. This keeps the pre-painted walls clean.

Goal: Grasp how the creased flap effectively prevents paint overspray from marking walls.