Libraries exist to preserve society's cultural artifacts and to provide access to them. If libraries are to continue to foster education and scholarship in this era of digital technology, it's essential for them to extend those functions into the digital world.
Many early movies were recycled to recover the silver in the film. The Library of Alexandria - an ancient center of learning containing a copy of every book in the world - was eventually burned to the ground. Even now, at the turn of the 21st century, no comprehensive archives of television or radio programs exist.