"The customer is always right ... except in software development."

Consider when:

Expectations != Specifications = Implementation

In what other industry do you hear the mantra "reset the customer's expectations"? In other words, convince the user/customer to accept the specifications (and thus, the code-to-spec. implementation, and limitations thereof) as what he/she actually wanted/expected/paid for, rather than the developer/vendor changing the specification & implementation to match the customer's expectations (however reasonable or unreasonable that may be). Technically, the latter isn't rework ... it's new work. And isn't new work billable?

Here's a better mantra (loosely) lifted from Beck's "Extreme Programming Explained" [1,2]:

"Don't resist change. Embrace it."

On the other hand, perhaps the Borg were right:

"Resistance is futile. You will be assimilated."

-- Robocoder