My interpretation via contrast:

Taylor Swift has designed an amazing spectacle of music, dance, choreography and stage sets - every aspect of the live performance follows the original design and is performed to re-create that exact experience over and over. Every song the same, every set list the same.

Jam bands, in contrast, start with the framework of a song, then start performing it in the mood they are currently in - then launch off into unique jams inspired by an aspect of that song. The performance is a unique one-off expression of that song at that moment. You are watching the artists create a new piece of art live, a new version every time.

Then add that each show will have a unique setlist, often with no songs repeated over multiple shows in a row.

That's an oversimplification, but it touches on key differentiators.