The product vision doesn't have to be clear
It's a bold thing to say, but I'm increasingly coming around to the idea that the product vision doesn't have to be perfectly clear.
An approach where the product vision is distinct in the long term helps the product manager break the habit of clinging “right here and now” to some ideas; concepts and beliefs from the "bright future" that inspire false confidence and stability in all of us.
The reason is simple - the future is deceptive, impossible to predict and always slipping away, and its ideas, concepts and beliefs, while you run after them all this time, can become obsolete or irrelevant by the next checkpoint.