He always entered via the ventilation system rather than the main lobby because the main lobby was patrolled by robots whose job it was to quiz incoming employees about their expense accounts.

More from Mostly Harmless

• A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
• All you really need to know for the moment is that the universe is a lot more complicated than you might think, even if you start from a position of thinking it's pretty damn complicated in the first place.
• Besides, she told herself, taking a deep breath, if life had taught her anything it was this: Never go back for your bag.
• "Don't tell me about the future," said Ford. "I've been all over the future. Spend half my time there. It's the same as anywhere else. Anywhen else. Whatever. Just the same old stuff in faster cars and smellier air."
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