A team can describe in detail what it intends to build and why the design is elegant. Asked who the users are and what they need from the service, the room goes quiet. What does the Service Standard say about that position?

The principle — being able to describe what you are building is not the same as being able to say who it is for.

Why the key is correct — the Service Manual states it plainly: If you do not understand who they are or what they need from your service, you cannot build the right thing. And the first point of the Service Standard is to Understand users and their needs A team in this position has a design and no answer to the question the standard puts first.

Why the others are wrong — writing the need down after the build starts produces a justification rather than a direction, since by then the answer cannot change anything. Internal clarity is agreement among non-users and can be complete while being about the wrong thing. And letting post-launch requests define the need hears only from the people who stayed, and hears them in the form of solutions.

Remember this — elegance is not evidence, and a design nobody can attach to a user is a guess.

Sources — the UK Government Digital Service Standard and Service Manual.