Vince Mancini explains:

As much as someone getting hit in the groin in real life is instant, automatic comedic gold, I’ve long maintained that having someone get hit in the nuts during a movie trailer is all the proof you need that that movie is going to suck those same balls. It’s sort of like when a band has an album, and the first single has both the same name as the album and is the first song, you know that’s the only good song on that album (I call it the “Are You Gonna Go My Way” effect). Anyway, our video editor, Oliver, has put together a compilation of movies with groin trauma in the trailer and their resulting RottenTomatoes ratings (we know those are far from scientific, but they’re still fun).

Further evidence: Jackass 3D, of all movies, didn't stoop that low in its trailer and it received a respectable 62%. It was one of the best nights out I've had in a long time.

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