People conflating practical fixability with blame. Suppose something bad happens, and the person who is morally speaking most blameworthy is someone who it is practically speaking impossible to induce to modify their behaviour, stop doing it, fix the problem, whatever. In that situation you might regretfully have to approach somebody else involved in the problem, whose fault it either isn't at all or is significantly less, explain why the problem can't be solved in the ideal way, and ask them nicely to modify their behaviour instead. What you do not do is to go to that person and rant and rave at them self-righteously as if all the moral fault from the original situation is theirs!