Once, I had to organize a meeting to propose a big reorganization of the supervision of our main software. There were some functional changes et some UI changes. I was inpired by the story about Steve Jobs and the calculator. I have brought a prototype where I could change fonts (size, boldness, italics, color), some text and tooltips. This meeting was a success. The stakeholders were happy to have influenced the UI. All the functional changes were accepted. No further roundtrip.