Painting, dance, music, etc...are forms of communication that are not verbal. Artists are attempting to communicate via means besides the spoken word. Anyone who comes to art as a deconstructionist ("it means whatever the viewer/listener wants it to mean") destroys the communicable genius of the product and cheapens the communication ability of the artist. If one was to approach the spoken word (another form of communication) as a deconstructionist ("I can interpret what you say however I want"- "it means whatever the listener wants it to mean") you and I would not be able to communicate effectively with one another (what's in my mind would not effectively or accurately be transmitted to your mind).