So when a project fails, who gets fired or who doesn’t get paid?
When a job isn’t done properly and a customer decides to go somewhere else, who is impacted apart from the customer and the shareholders?
Or when an employee leaves to work somewhere else because a promise wasn’t delivered as agreed, is their manager impacted any more than having to hire a new person?
Lack of real accountability means that people will typically deliver their best efforts, not an actual outcome.
Delivery is hard, making people accountable will ensure they add that little bit of extra effort required to ensure an outcome is achieved when things get hard.
And if they aren’t happy being accountable or going the extra mile sometimes, then they aren’t really the people you need are they?
(But remember being accountable applies to you to)