Rack focus

Racking focus pulls the lens from a near subject to a far one, or the reverse, so attention moves while the camera keeps rolling. It needs shallow depth of field to read at all, which means a wide aperture and usually a longer lens. Film sets employ focus pullers for exactly this. Doing it by hand at f/1.8 while also framing and talking is awkward. Creators use it to reveal a product behind the presenter, to switch between two people in one frame, or to end a beat without a cut, and overusing it draws attention to the camera work rather than to whatever is being revealed.