The brief is the design
By the time the brief is right, most of the decisions have already been made.

By the time the brief is right, most of the decisions have already been made. This is not a clever line; it is an observation about where the difficulty actually lives. Once you can say what the thing has to do, in one sentence, in words the client would use at home, the visual work becomes a matter of craft rather than search.
Most bad briefs are bad in the same way. They describe a mood instead of a job. "Premium but approachable" is not a brief, it is a horoscope. "The label has to be legible on a bottom shelf under supermarket lighting from a metre away" is a brief, and it has a right answer that you can test.
Clients occasionally find this frustrating, because it looks like nothing is happening.
We spend the first week arguing about the sentence. Clients occasionally find this frustrating, because it looks like nothing is happening. What is happening is that we are deleting about sixty per cent of the possible design space before anyone has drawn anything, which is the only reliable way to make weeks three to six calm.
If the brief cannot be written in a sentence, that is information. It usually means there are two projects wearing one coat, and the honest move is to say so before the invoice rather than after it.