Chase Alias' Monkey Around :)(: An Obligation to Beautify (Explored) a video by Chase Alias :)(: on Flickr.
The "public" in public art actually refers to a personal space. It does not contain an artistic value judgement. It does not serve the public. It was not created for the public. It could be targeted at the public, but it could completely ignore the existence of a public. Here, art has simply made effective use of a public spatial environment. It does not have an obligation to beautify or to adorn.
Ai Weiwei. Ai Weiwei's Blog: Writings, Interviews, and Digital Rants, 2006-2009 (Writing Art)