Businessweek's Brad Stone has written a lengthy cover story on Amazon that opens with a bit about Bezos' email style and shows how important customer service is to him.
When a customer sends Bezos an email complaining about something Amazon-related, Bezos forwards the message to the appropriate person at the company. The only addition Bezos makes to the email is one character:
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The recipient then scrambles to solve the issue and must get his or her reply approved by multiple people before responding to Bezos.
Stone writes:
"When Amazon employees get a Bezos question mark e-mail, they react as though they’ve discovered a ticking bomb. They’ve typically got a few hours to solve whatever issue the CEO has flagged and prepare a thorough explanation for how it occurred, a response that will be reviewed by a succession of managers before the answer is presented to Bezos himself. Such escalations, as these e-mails are known, are Bezos’s way of ensuring that the customer’s voice is constantly heard inside the company."