A positioning that holds.
Not a strapline for the wall. Not a big idea for the brief. A measurable perception in the visitor's mind — put into one sentence everyone on the team can say.
The visitor understands why they should come to your stand. Why they're investing their time right here. Why their problem gets solved here, their pain heard here. And internally: management, stakeholders, the board and the team on the stand — everyone says the same sentence, because they understand it.