Even if the government officials were so distressed by the costs of the economic sanctions on their people that they offered to step down, who would be an acceptable replacement? Some puppet ruler that would sell the country to multinational corporations so they can exploit its resources and people?

One of the problems with democracies is that they're really hard to get started. There are a lot of institutions that need to be in place before they really work, and rushing right to elections just ends up with the same old assholes staying in power because that's all anybody knows.