Why are the physical representations of LeWitt's work usually temporary?

This meditation on transitory art begins with Sol LeWitt. His

conceptual art is representative of a large strain of creative endeavors that emerged after 1950. To this day it engages artists, gallerists, collectors, and museum curators worldwide. "Ownership" of

his art was not always evidenced by possession of a physical object

like a painting or a sculpture, but by possession of documents-a

certificate of authenticity and a diagram in the case of LeWitt. Together these documents contained (typically partial) instructions on

how to fabricate or install his work. Possession of a certificate and

diagram gave their owner a guarantee of provenance and the authority to arrange for installation of the work with the artist or the

artist's successors in interest-nothing more.' In addition, the actual installations of such works typically were not accomplished by the artists who made the certificates and diagrams, the artists as temporary, movable, or destructible after their installation. Such projects were distinctly different from routine art sales by galleries or auction houses. Rather than obtaining a painting or

sculpture, a buyer obtained only the right to seek its creation and

installation. It was the creative plan that was the artistic product,

not an extant creative work.

Explanation:

answer; timpani,horns and bells;

i need