“Improvisational performance in dance (like improvised performance in other media) fundamentally seeks to change the audience’s assumptions about what a dance piece might be.” Sophie Lycouris BA, MA, Destabilising dancing:tensions between the theory and practice of improvisational performance, 1996, pg 177-8.
I would propose that was merely one goal for western white concert dancers early on, when they “discovered/invented” improvisation.
Such a “goal” could be said to be the first step for many dance-makers. “Oooh, look at me I’m improvising!” Great, now what? What about improvising are you going to reveal to me? What are you going to do with it? Is it a means? Then what are you meaning? Is it a tool? Then what can you show me about the tool?
I think many people use an improvisational approach to time and the creative process for many other reasons. To ascribe a goal to a temporal tool seems a bit much.