My way of thinking art is that it will basically be and should be created for an audience rather heterogeneous and for that matter multiple readings will be perceived. Consequently, the artwork must contain different layers for these wide audiences. Sometimes even different meanings and contradictory ones are intentionally worked on top of each other. That is the beauty within, the deepness of it.
I'm not implying that art should be somewhat hermetic nor easily understandable. I'm affirming that is must lead to a dialogue between artist and viewer and between viewers themselves.