Graffiti is a voice claimed when no other is given: the ultimately democratised language, subversive, irreverent, free. So often, we wonder why people will not engage, why they will not comment, question, or challenge. But that may be to miss the point. The challenge may not be that people are not engaging, but rather that we are failing to listen in the right places.
The graffiti of organisations is written in social spaces: a claimed permission to comment or criticise, reflect and shout. By claiming a scrawled voice, we can shrug off the implied consequence or oversight of any formal power. If you want to learn what a community is really thinking, search for the graffiti.