But dictatorships are stable. Until they aren't, but Who Could Have Predicted? and being unpredictable you don't have to budget for it and once it happens it is someone else's problem.
In a democracy you have to pay off a lot of groups that you could otherwise pretend to be be able to safely ignore. Of course for the long term viability of a project having to deal with objections before they trigger a revolution is a plus. Are you under the impression that our planning structure is overly concerned with long term viability?