It's the system that determines how its run, not the people at the top.
That is the catch. It only determines how it is run if the people at the top are following the system. The system is supposed to determine that, but if everyone in positions of power decide to disregard what the system is supposed to be, then suddenly the system that a government used to have or advertises as having, no longer represents the actual state of affairs.
Responsibility means owning an outcome. If I take responsibility for the safety of your children and a meteorite literally falls out of the sky and kills them, I am still responsible. I'm not going to try to make excuses and make sure you know it wasn't my fault and there wasn't anything I could have done. I was responsible. Your kids are dead. The buck stops with me. That's what actual leaders do, they own the outcome.