Every week, Saturday Night Live performs its whole show twice. At 8 p.m. the cast plays a dress rehearsal for one live audience. At 11:30 p.m. the show goes on air in front of another.
In one writer’s account, about 45 sketches are read on Wednesday. Eleven to 13 are performed at the dress rehearsal, and two or three of those are cut before air. An SNL editor explained: “Our sketches will live or die by the reaction of the audience.”