Four things, written down
Who it is for. What must be true on day one. What can wait. How we will know it worked. If those four lines are missing, we are decorating, not scoping.
The brief is a product
We treat the brief as something you can argue with in a room. It changes when the work teaches us. It does not vanish into a slide that nobody opens again.
When the brief is honest, design has a job, engineering has a path, and after-sales has a definition of ‘working’. The test is whether a stranger could run the project from the page.
