The plain simple truth about people who have great thoughts is that there is absolutely no accountability. There is no one saying- You are late, you need to fix this, you need to get back on track. If the thoughts just stay in your head ultimately you remain unaccountable and unfruitful. When you write and share your vision people will ask you about it and you want to be able to tell them that you have made some progress. When you share your progress you are able to garner other energy versus no one knows what you’re thinking, no one knows how to measure it, and no one knows the timeline.
That is why a written vision makes sense. It is the same reason people love sports in America because there is a winner and loser and statistics for every game. If you throw out the stats and the scorecard, it takes away the accountability, the measurement, and ultimately the fans.