Union Square Park NYC - street artist creating sand mandala
As per Wikipedia: The Sand Mandala is a Tibetan Buddhist tradition involving the creation and destruction of mandalas made from colored sand. A sand mandala is ritualistically destroyed once it has been completed and its accompanying ceremonies and viewing are finished to symbolize the Buddhist doctrinal belief in the transitory nature of material life.
All that effort, all that work and poof...it's gone. But the joy according to the artist was in the creating!