Great art is often the result of great struggle, and though no two scenes are exactly the same, we can perhaps most readily measure a scene's difficulty by the number of takes needed to get it right.
Or from another perspective, some filmmakers are simply tireless, infuriating perfectionists who don't know what they want until they see it for themselves.
The time-sensitive, high-pressure nature of movie-making means that directors and actors typically have a finite window in which to complete a scene, though in the case of these 10 movies, the filmmakers went wildly off-piste, running scenes again and again until they were supposedly just right.
Naturally most of these examples are the result of clinically obsessive filmmakers who didn't know when to reasonably call it a day, but in some cases the end product explicitly justifies the effort, and in a few select instances, it was even the actor's idea to keep pushing for yet another take.
Whether high-end set-pieces or most basic dialogues, these scenes were all forged from hours and hours of back-breaking on-set labour...