We used to have waterfall projects where everything is specified upfront and tried to describe a system we don't know about. My point is not to go back to that

We used to have waterfall projects where everything is specified upfront and tried to describe a system we don't know about. My point is not to go back to that but just to think deeper about the high level problem to give more directions about a solution the project manager already know about (or can ask the customer during meetings). That just try to prevent useless iterations which doesn't enhancement the solution through a better understanding of the problem but fix communication issue because people with different background don't know how to communicate.