One of the best things about working with software is that it can be designed and built so that it's flexible and adaptable. Real-world physical objects are limited by their design and construction: The minivan my wife uses to take our kids to school can't morph into a sports car or a school bus. Software systems such as Exchange Server, on the other hand, can be deployed into a wide range of environments, but this flexibility raises the question of whether the software is being deployed properly. Not every administrator is aware of every nuance of Exchange setup and configuration. Microsoft has worked hard to build a product that "just works" in most situations, but it requires a fair amount of specialized knowledge to examine an Exchange server and see whether it's optimally configured.
As a secondary problem, consider what happens in midsized to large organizations. Humans aren't very good at repetitive tasks. Sure, we can do them, but tasks that require both attention to detail and repetition are especially difficult because we're easily bored. If someone walked into your office and asked you to examine every aspect of the Exchange configuration on one server, that wouldn't be too bad. On 10 servers, it would be somewhat tedious; on 400 servers, you'd probably go mad. . . .