Anyone that's been around Agile for a while has probably heard of the Design the Box exercise. The idea is to help the team define and understand the product vision.
I'm getting near the end of a project. We've had some challenges in terms of making the right decisions on scope. This has manifested itself in completing user stories only to have the business team say "I know that's what I asked for, but I don't think it's right." We didn't do a Design the Box at the start of the project.
However, as they start implementing their organizational change management approach (this tool is going to a large set of users), they are developing some communications tools including a web portal and a set of posters. These posters are 2x3 feet, have a logo and the tool name on the top, and more information below. They are going to be posted around the buildings where the target end users work. As I looked at this it hit me, if we had created this poster at the start of the project, we may have avoided some of the challenges we encountered.
So next time you're starting a project, think about what the poster might say.