Cinema and television, though inspired by the plays of ye olden days, are different. True one could make a play for almost any movie made, it doesn't have the same aspects that a movie does. The way the lines are rehearsed once allows for greater precision and greater emphasis on the visuals.
Cinema started without words at all, at most it would have text flash on the screen.
The image was more important than the speech, which a play lied extensiveley from. You rarely see a play that has a gap without speech lasting more than a minute.
In this sense, cinema borrows more from painting than playwrighting.