My summer job at age 16 was selling Godiva chocolates in the local mall. My manager there told me, "Don't just read the descriptions on the brochure; eat every kind of candy we're selling so you can describe and recommend them to customers." I happily complied. A variation of that principle is used at Microsoft. It's not quite as delightful as taste-testing truffles but serves a similar purpose.
In what is called "Eating your own dog food," Microsoft employees use test versions of all the products on a daily basis long before they come out. Windows 95 marketers used the new operating system every day for months before it was finally ready for market. Teams working on everything from Word, the word processor, to the Encarta CD-ROM encyclopedia do the same thing.
Eating your own dog food is not always pleasant. When Microsoft rolled out its new e-mail system to tens of thousands of employees, there were delays, computer crashes, lost mail and lost productivity. In one glitch, the computer e-mail screen would freeze up for 45 seconds and then go back to normal.
"Eat your own dog food, but don't believe your own press releases" means use the product for yourself, rather than read all about its great features in a press release. See what it's like to be a customer, and you can empathize with them, understand their needs and frustrations. Microsofties use this experience to know the product they're developing, testing or selling inside and out.