Mastering the Requirements Process: Getting Requirements Right, 3rd Edition

11. Non-functional Requirements

in which we look at the requirements that specify how well your product does what it does

How can something called “non-functional” be important? Consider this, a story that really happened: The client rejected the delivered help desk software. The functionality was correct—it supported the help desk’s activity, and did all that it was supposed to do, but the client didn’t want it. Why not? Because the users—the help desk operators—refused to use it, preferring to use the existing manual procedures. Why was the product so bad? Because the requirements team had paid almost no attention to the non-functional requirements.

Why was the product so bad? Because the requirements team had paid almost no attention to the ...