Intentional by definition means to be done deliberately, on purpose. It is hard to say art is anything but intentional because even if a piece does not turn out quite as the artist imagined, even if it becomes something completely different, it still began with the intention of being art.
On the other hand, it can be argued that art can become art after it is created. Most people would not call an old, caved-in sofa a piece of art, but it could easily be put in a gallery and entitled “Attack of the Couch Monster”. And people might pay to see it.
I still believe that such art is intended because someone had the idea to call it art, so it has reason to be art. There. It becomes intentional. After all, art is an idea that is physically manifested.
Generally, when referring to art, representational means that art depicts something recognizable from life, nature, the universe. In that sense, I do not believe art has to be representational. To dismiss nonrepresentational, fantastical designs and paint splatters would be to dismiss things that can only be created as art. I personally would not want to live without such things. So please, never tell me art must always represent what I can already see.
Art is flexible and it evolves. It reaches into anything it can get itself into. Painting, writing, cooking, architecture, film. It is anything we create to communicate an idea, a feeling, or a certain taste. It is the physical manifestation of an idea or a concept. I cannot think of a single human thing, furniture, cars, clothing, containers… not one thing that was not designed and created. Even this world was created. Define art as you will, and I will probably agree because I think art is everything.