TLDR: Any task assigned to nobody, or to multiple people is all but certain to fail. If you care about seeing a task or goal completed, it must be assigned to one person. Not zero. Not a group. One. Individual.
Can they delegate it to someone else?
Sure. But they are still responsible.
Can they change the requirements?
Sure. But they must justify it.
When no one is responsible, or a group is responsible, the outcome is always the same, nothing happens.
It’s true for emergencies.
It’s true for broken windows.
And it’s true for your business.
So make sure the most important work is always assigned to a single responsible person to maximize your chances of success.