" Not often—with six-letter passwords a hacker had a better chance of winning the lottery than randomly guessing a particular password. Since the computer hangs up after a few log-in failures, the attacker would need all night to try even a few hundred possible passwords. No, a hacker couldn’t magically enter my system. He’d need to know at least one password. "

― , The Cuckoo's Egg: Tracking a Spy Through the Maze of Computer Espionage