The idea of "unaccountable" failures only makes sense if both (a) the problem is so systemic that actually an executive is accountable, (b) the executive is so far removed in the hierarchy from the line employees doing the work that nobody knows each other or sometimes even sits on the same campus, (c) the levers available to the executive to fix the problem are insufficient for fixing the problem, e.g. the underlying root cause is a culture problem, but culture is determined by who you hire, fire, and promote, while hiring and firing are handled by "outside" HR who are unaccountable to the executive who is supposedly accountable. But really this is another way of saying that accountability is simply another level higher, i.e. it is the CEO who is accountable since both the executive and HR are accountable to the CEO.
No, you have to have an astoundingly large organization (like government) to really have unaccountability sinks, where Congress pass laws with explicit intent for some desired outcome, but after passing through 14 committees and working groups the real-language policy has been distorted to produce the exact opposite effect, like a great big game of telephone, one defined by everyone trying to de-risk, because the only genuine shared culture across large organizations is de-risking, and it is simply not possible to actually put in place both policy and real-life changes to hiring, firing, and promotion practices in the public sector to start to take more risks, because at the end of the day, even the politicians in Congress are trying to de-risk, and civil servants burning taxpayer money on riskier schemes is not politically popular, though maybe it should be, considering the costs of de-risked culture.