What do audiences want?

To be entertained
To be moved
To be transported
To be amused, amazed and bowled over
To hear familiar tunes
To hear rarely-performed repertoire
To learn something new
To be challenged
To have a “bespoke concert experience”
To enjoy whatever is on the programme
To feel the musician’s concentration and communication
To sense the synergy between ensemble players, or orchestra and conductor
To enjoy a concert in an unusual venue, by candlelight
To get up close and personal with the musicians
To applaud whenever they like
To exclaim at the soloist’s beautiful gown
To see more young people in the audience
To dress down
To dress up
To sit in comfy seats
To have value for money
To meet friends & have interval drinks
To have time for dinner beforehand – or afterwards
To not have to get the last train home
To not be patronised or treated as uneducated or ignorant
Performers can never please all of the people all of the time and usually need to balance their desire to play certain repertoire with the expectations of the audience. Personally, I don’t think performers should ever feel the need to pander to an audience 
Some actual audience views
…..quality, enthusiastic performances (not robots) and a diverse mix of repertoire

[I want] An ineffable mix of emotion, technique… and always something new. I want to be moved, educated, entertained, and astonished!
And some actual performers’ views:
……communicating. I want them to know and feel what I’m feeling in the amazing music

Audiences want to feel that they are engaged in the performance, that they are part of the communication. I think primarily they don’t want to feel patronised or bored. It’s probably easier to say what they don’t want. I think it also depends where you’re playing. In a village church with an audience who like classical music but might not want to feel challenged, you’d play something different to what you might do in an inner city concert hall……. different audiences want different things but ultimately they want to feel part of what’s going on.
This debate will run and run, in tandem with the endless hand-wringing and eye-pulling about the death of classical music. There is no simple answer. Maybe, as this article suggests, it is time classical music became more radical, to stop chasing audiences or worrying about ticket sales, and to simply revel in “great, challenging and rewarding music”. An idealistic view perhaps, but certainly one which merits consideration.
Why do I go to concerts? Because I love the uniqueness and excitement of a live performance, the sense that it is a one-off, created there and then (of course, as a musician myself I also appreciate the many hours of careful practising that go in to creating that performance). I love the sense that this is a shared experience, but one from which we can each take something personal and special – and that, for me, applies to all concerts, regardless of performer, repertoire or quality of performance.
As a performer, I believe the music was written to be shared and for me that is the fundamental motivation for performing.

Further reading
Issues in Planning Concert Programmes by Hugh Mather (who runs the excellent concerts at St Mary’s Perivale)