The sand mandala's most striking and best known feature to outside observers is its deliberate impermanence: once complete, and after the ritual period for which it was constructed has concluded, the mandala is ceremonially destroyed, swept together by the monks who built it in a formal closing rite, an act the tradition treats as itself a central teaching rather than a regrettable end to painstaking work, embodying directly and physically the Buddhist doctrine of impermanence, anicca, that days of exacting labour can be dismantled in moments, and that even the most beautifully rendered form is not meant to be clung to.
The swept sand is traditionally distributed, some portion typically carried to a nearby body of flowing water and released, understood as carrying the mandala's blessing outward into the world and to all beings the water eventually reaches, a closing act that extends the mandala's ritual purpose beyond its own physical construction and destruction. Public sand mandala constructions, performed openly over several days in museums, universities and cultural centres worldwide since the later twentieth century, have become one of Tibetan Buddhism's most visible and widely attended forms of public teaching, undertaken by monks, notably including monks of the Namgyal Monastery and other institutions with Dalai Lama affiliation, specifically as a way of sharing Tibetan Buddhist practice and the teaching of impermanence with international audiences.