A certain strangeness exists in the tripart relationship between a person, a sign (the creative work, for our purposes), and the thing or things signified. In his theory of poetry William Empson simply calls it ambiguity (Ibid). Walker Percy calls it the Delta (Δ) phenomenon (The Message in the Bottle, 30-45). Noam Chomsky describes a curious language acquisition device — his mysterious "black box" that inputs linguistic data and outputs sophisticated language (Kathryn Hirsh-Pasek, Roberta Michnick Golinkof, The Origins of Grammar, 31). Charles Sanders Peirce called it thirdness (A Letter to Lady Welby, 1904).
It is part and parcel of the artist's task to engage that sensibility to thirdness or ambiguity. Whether one is crafting a piece of fine cabinetry, a choreography, a menu, a novella, a tapestry, or a film, the artist's idea is made of such stuff that it can't be exhaustively mapped or spoon-fed to its audience. Perfect transparency is exclusive of artistic meaning. This is why theories of opera or cinema that describe the music or the drama as additives filling in one or another perceived "gap" are incorrect — the combination of media engages an altogether different set of symbolic mechanisms, as opposed to a more complete one.
Artists have from time to time attempted to devise systems or recipes for a desired ambiguity. Umberto Eco has written much about the meaning of "openness" in artistic endeavor to this end. Eco describes openness in terms of musical works of the mid-twentieth century (referring to the then much in vogue practice of composers of "serious" music allowing for performer-directed outcomes in their work) and identifies a "fresh advance" and a "completely new problem" while at the same time acknowledging the obvious, that all works of art are open to interpretation (The Open Work, 8, 13-14). We are told:
Berio's Sequence, which is played by different flutists, Stockhausen's Klaviersück XI, or Pousseur's Mobiles, which are played by different pianists (or performed twice over by the same pianists), will never be quite the same on different occasions. Yet they will never be gratuitously different. (Ibid., 13)
The same could be said of any performance of any piece, which Eco acknowledges, while noting that these works are self-consciously open in a "far more tangible sense" (Ibid., 3). Some of them seem exercises meant to consciously skirt the ambiguity question altogether, by making it built-in such that there can be no questioning of intent, because the intent is purposefully mutable. We are given the shell of a piece in which the composer participates up to a certain point before tossing the thread of the idea into the wind. It is then up to the performer or the listener to give the body a soul and to make Frankenstein walk and talk.