One of the things that impresses me about street art, quality street art, not just mindless tagging and graffiti, is that it is free to whoever wishes to look at it. It is not purchased and hidden away in private collections, or in galleries that charge admission to view. In a lot of cases it is vibrant, original, witty, confronting, challenging, opinionated . . . and is not one of the purposes of art to make people look at something in different ways, to force the viewer to question and think?
"The principles of true art is not to portray, but to evoke."
- Jerzy Kosinski
Compare with pic below - before and after: