So imagine a contiuum under the rubric “good music.”
On one end lies a point entitled “spontaneously composed”.
On the other end lies a point called “pre-conceived.”
Here’s the rub: All music is improvised.
Yes, all of it. Improvised. That is “made without preparation.”
Even the pre-conceived? Yes, because you can’t prepare for every eventuality. It’s simply impossible. Life will intrude.
But the beauteous part is that it’s all of a piece. Whether thought up here on the spot, or conceptualized at an earlier instant. It’s all “good music.” (or the converse)
And the more this notion is embraced, the more both ends of the continuum are enriched. The end called “spontaneous” is made sharper and lent more concision. It’s made more like a “composition.” And the end called “pre-conceived” is made more life-like and surprising. It becomes like something thought up right here and now. Both ends benefit from the presence of the other. Because practically speaking, everyone just wants to hear good music.
So who’s to say ‘improvisers’ shouldn’t play something that sounds familiar? or something short? or something that sounds ‘pre-thought’?
And who’s to say ‘interpreters’ shouldn’t “take liberties”? or play a familiar piece in a way that renders it strange or ‘incomprehensible’? or play someone else’s piece in such a way that it sounds like the performer wrote it?
Not to be trite, but isn’t life an improvisation? And if that is the case, then isn’t everything emanating from life/us, also an improvisation?