I think you're wrong about art on most levels. What your describing is a very narrow idea of art. Art absolutely can mean making whatever you want. I agree that if an artist wants to convey something and fails to do so, then they've failed in that artistic endeavor, I think thats the only way to measure something so subjective. But that doesn't make it not art, it just makes it bad art. A child scribbling on the walls is art just as much as Banksy creating finely honed graffiti. A cook frying meat for the fun of it is still a cook, they've still cooked food, and that's all being a cook is. Doing something badly doesn't mean you're not an artist or a cook, it just means you're bad at it. But philosophers have been debating the meaning of art and what makes art art for probably as long as there have been philosophers to do so. I don't think we're going to find any consensus on the subject here.
