I don't understand the perspective you are asking this question from. But, my responsibility would be to follow my boss' vision. If it has clear and achievable goals, then it's easy for me to figure out what to do. Visions which are too broadly scoped won't have clear and achievable goals. Visions which are too narrowly scoped is micromanagement.
I might not always agree, but in those cases I will voice my ideas / concerns. After I know I've been heard out, I will defer because it's my boss' decision to make, not mine. As long as my concerns are heard and integrated into the decision, then I should be content.
> I don't disagree, but now you seem to claim something else. Originally you just wanted a strong vision with goals, regardless whether the employees agree. Now you want buy-in too.
There's a clear delineation between leadership -- aka, vision-creation -- and implementation. My original opening of "as an employee" was meant to frame the remainder of my comment as from the perspective of someone responsible for implementing a vision. The remainder of the discussion has been about the leadership side, or how to create a vision in the first place. If you are creating a vision with a group, you need buy-in from the entire group. If you don't, then individual leadership will walk away with differing interpretations and goals, which is what leads to dysfunction. These separate visions will then be pushed down the line, and you will have implementers working at cross-purposes, political infighting, etc.
This ~~synchronicity~~ synchronization on the leadership side is the important part. If a unified vision is being clearly pushed to all the implementers, then the collective action will result in a singular vector towards the vision. If unclear or even competing visions are being pushed, then you won't get collective movement because all the individual actions will be moving towards different results.
> And there is also principle of subsidiarity. If people strongly disagree on the vision, they can come to some compromise where they realize each vision in their own domains.
It's one thing to acknowledge that there are two potential solutions, and as a group decide that both will be explored. It's a completely different situation to have two groups that can't come to terms and are therefore competing against each other.
EDIT: Big words are hard. Let's go shopping.
I don't disagree, but now you seem to claim something else. Originally you just wanted a strong vision with goals, regardless whether the employees agree. Now you want buy-in too.
And there is also principle of subsidiarity. If people strongly disagree on the vision, they can come to some compromise where they realize each vision in their own domains. (As John Carmack put it: "if you are not sure, explore both solutions".)