“Not knowing the full requirements is agile“, an old boss of mine told me in the past. As soon as I heard it, I freak out! I couldn’t believe it! I was so frustrated that I don’t know how I managed to keep my mouth shut! Lacking functional requirements is a recipe for disaster. A way straight to hell. You can’t build a system if you do not know how it works. Agile doesn’t alter the need for functional or other requirements, but it does change how you gather them. The waterfall way is to go through a long process of documents filling and revising them, till they contain all(?) the system’s requirements. The agile way to gather requirements is to specify the requirements for a small increment of the system, a minimum viable product as it is usually called, build it, then get feedback and work on the next increment. No matter the way the phrase “I don’t know” is embraced, should never be acceptable! Without the right context anyone might understand anything!