I remember as a kid turning up the volume as it was fading wondering if I’d hear them stop. I always thought of the fade out ending as a lack of creativity and decisiveness, let alone the question of how do you do a fade out ending in concert.
Now really, can you imagine an artist or a band writing a song, coming up with a great intro, verse, chorus, fanci-fied guitar solo, cool drum fills and maybe even a bridge after the solo and now they’re in the studio recording their song, going through the last chorus and they start looking at each other with a puzzled look like …uh…what do we do now?? At that time the recording engineer picks up on the fact that they didn’t plan an ending so he starts motioning a rolling gesture with his hand to keep on playing the last four measures as he slowly pulls the faders down. Then with a big smile on his face motions them to stop and says, “Did you hear that fade out? It was all me,” and never gets any credit for it. Or maybe he didn’t even tell them… they could still be playing.