Doctors in the Netherlands, where euthanasia is lawful, are in trouble because they euthanized a demented woman who at that moment was uncooperative. She had previously given them instructions to do so, but it was not done in the proper legal form.

I agree that the system should be very careful to prevent people from being killed unwillingly. At the same time, if the system investigates small failures like this one, that gives me the impression that overall it is very effectively careful.