I'm involved with a non-profit called NEXT Ensemble and we have an "audience engagement" meeting tomorrow. This has led me over the past few days to think hard about what I think ought to be the first question:
Why should anyone actually go see live music?
Let's be honest, there's very little reason to leave the house for entertainment in the age of Netflix, Spotify, and YouTube. There's more available to stream than anyone could possibly ever watch/listen to in one lifetime. So why bother to put on pants, drive to the venue, buy a ticket, find a seat, etc etc etc.? And besides, what if it isn't any good? A waste of your time and money? You're pretty much stuck there. But if something's not to your liking on Netflix, you can just move on to something else -- you've invested very little in the experience.
And besides, watching a show on Netflix or listening to a piece/song on Spotify, you're guaranteed a certain level of quality. The product you are taking in is a finished, polished one -- as close to perfect as its creators could get it. The next time you seek out that show or song, it will be exactly the same.
I have a theory that this is why there are so many of the same fast-food restaurants at major highway exits -- no matter where you are in the country you can rest assured that there will be no culinary surprises: a Big Mac in Tulsa will taste exactly the same as one in Nashville or San Diego. To eat at a local restaurant comes with no such guarantees -- sometimes you'll be disappointed, but sometimes you'll be amazed when you live dangerously.
Performing live is a dangerous thing. Something will go "wrong," no matter how prepared the performer is. Even if the performance is note-perfect, there are too many other variables to guarantee one performance will be the same as the next.
And that's what makes it exciting. Those unknowns are why live performances are different from recordings. With recordings, you can (arguably) repeat the exact same moment over and over again, but live, there is no such security. Something will happen that is unplanned, and everyone has to deal with that.
I'll bet you thought I was speaking from the performer's perspective in the preceding paragraph, but I wasn't. For audience members, sensitive to all of the things that make up a musical moment (which are far more numerous than just the notes being played/sung) the absence of repeatability and potential for disaster/astonishment is what makes going to a live show worth heading out the door, buying a ticket, and putting on pants.