Brewster Kahle, founder of the Internet Archive:
It turns out that the World Wide Web is very fragile. At the Internet Archive we collect one billion Web pages a week and we’ve discovered that Web pages last only about 100 days on average before they change or disappear. They blink on and off in their servers, gone forever unless someone has thought to preserve them. So the Web lacks a memory, an enduring archive of what has transpired there.