"It's an interesting that this seldom happens in theatre, music or literature but often happens in film, comedy and speeches." It happens all the time in music

"It's an interesting that this seldom happens in theatre, music or literature but often happens in film, comedy and speeches." It happens all the time in music. Songwriters are seldom as well-known as performers, and you could argue that they do the lion's share of the "authorship" of a given song. Most of them arrange the music and write the lyrics. It's a rare instance where a songwriter becomes prominent enough, in his or her own right, to rise to the fame and fortune of his or her star performer. For every Quincy Jones or Leonard Bernstein, you have 100 songwriters and producers laboring in obscurity behind big-ticket artists. (In fairness, though, highly successful songwriters earn residuals on their work, and thus tend to be handsomely rewarded. They get the fortune, if not necessarily the fame or the popular attribution). Theatre is an interesting exception to the general rule. Some of it is a function of time. We have every reason to believe, for instance, that William Shakespeare was less famous in his day than were the best-known actors who performed his work. But since there was no technology around back then to record the performances for posterity, the only things that survived were the written works -- attributed solely to the playwright. The rise of credit for performer, rather than writer, probably has a lot to do with the rise of the recording and media industries. In fairness, any truly great screenwriter or director will tell you that performers really do contribute enormously to the final product. A great screenplay is a great screenplay, but the finished film is a substantially different piece of work. A screenplay is to a film what an outline is to a paper, or what a wireframe is to a website. It's critical, but it's highly theoretical and open to myriad different interpretations. The interpretation that ended up on film, in this case, is the work of multiple "authors."