Sound designers are nerds, and so are we for creating this blog and reading it. So whether or not you are already in the loop this should seem somewhat familial.
In the 1950's a Gary Cooper film titled Distant Drums was in production. In it, a minor character named Wilhelm was to wallow in the water and be bitten by an alligator, screaming with agony. As is usually the case the on-set recording of the scream wasn't dramatic enough so the studio employed an additional dialogue recording session to beef it up. In the sound room a single take was recorded of a series of six screams (by an arguably anonymous voice actor). Among these six takes was the now famous sound-effect known as "The Wilhelm Scream."
At some point the scream was found in the Warner Bros. sound effect library and became a sort of badge of honor among sound designers. No matter how unfitting or inappropriate it was for the the scene it was considered a right of passage to use the sound effect in the project at hand.
Nowadays the joke has become Tarantino-style passe'. Apparently too much of a good regurgitated thing can get annoying. Even among nerdy sound editors that have been in on the joke for decades. And us?