The boss sends a memo announcing a new policy that some people in the team disagree with.
Disagreement with the new policy makes for some good water cooler conversation.
A couple of people reply privately
These that have the confidence to disagree, privately reply to the boss, and the rest remain quiet. Boss is happy to write a follow-up email that clarifies a couple of points.
There is still some disagreement by the water cooler.
A few people publicly react to the memo.
The boss addresses the replies, and some counter argumentation gets built. She is then forced to explain things from the beginning, and some whys emerge. Of course, there is still some uneasiness by the water cooler.
Come next Monday, a new person joining the team asks about that new policy over lunch. In any of the scenarios above, anybody in the team could explain him what it is. In the third one, there would also be a conversation about why it is that way.
Vision can be built through thoughtful manifestos and phrases on the wall, but those are usually superficial statements that just talk about outcomes.
Open, scriptless conversations in which the whys are shared, discussed, and reshaped create real visions: the ones that align teams and make them autonomous. The vision can then be brought to peers and customers.