If you are doing a marketing video in which you interview customers, let the customers read the brief before the camera rolls. It will help them frame the points you need. Otherwise, they’ll default to their own narrative.
If you are asking a freelance writer to write a brochure. Give them the brief. It will create context for the writing and story.
If decorating the office, give the designer the brief. It will guide decisions that support your business goals — not the designer’s portfolio.
If are tired of your homepage. Give the web designer the brief on the first day.
The brand brief is the most important tool a marketing company has. I know a CEO who shares the brand brief with every new employee.
There are a hundred uses for a brand brief. Use it every day. Plants need water.