“The repetitious aspects of his (Chaplin’s) performance – the squared – off turns, the hackneyed flourishes of the arms-were just as amusing as the pratfalls, which were themselves usually telegraphed far in advance. And there turned out to be a very particular kind of amusement, one not generally available before the twentieth century, in going back to see the same pratfall, which seemed in some cases to be all the funnier now that it was no longer a surprise.” Michael North, Machine-age Comedy (introduction) p. 4-5.
In this paragraph Michael North describes Charlie Chaplin’s repetitive comic routine as one of the main factors of his comedic appeal to the audiences. Even though one can argue that comedy should depend “on surprise” it has been proved that certain gags work better when they are repeated with an almost mechanical accuracy. ibid., 4. This is not only true in respect to silent cinema and early comedies. Just as Chaplin was always dressed in the same outfit and performed the same acts, a lot of sitcoms involve characters who perform the same routine each and every episode, be it a catchphrase or a signature gesture. In sitcoms, both animated and life-action ones, viewers expect to see same characters who look the same and do similar things from one episode to another. Although it may seem strange that repetitive jokes keep working time after time, since the audience knows exactly what the punchlines will be or what this particular character is likely to do in the next second, this type of comedic routine has proved to work for several decades now.
To give an example, there is a side character’s in The Simpsons, Sideshow Bob’s, repetitive gag of stepping on a rake. This comedic trope and Bob’s reaction to it (his signature growl) became one of the key characteristics of this hero. As you can see in the clip that I have attached, in one scene from the show, there is not just one rake, but many of them, and so the viewer watches how Bob steps on a rake after a rake, repeating his main gag several times in a raw. This is fun to watch not only because we expect to hear the exhausted growl after each strike of the rakes, but also since we do not know for how long the scene will last this time. Therefore, by repeating the famous gag many times, the creators of the episode play with audiences expectations by intuitionally exaggerating the already well-known and awaited comic routine.
You could expand more on the reason why repetitive gags work by engaging with some of Bergson’s claims that North discusses. Bergson’s argument about laughter’s purpose to “convert rigidity into plasticity” fits well here as it highlights laughter’s role in molding a character and possibly repressing patterns of repetition through “comic punishment.”