Why have peace efforts failed to end conflict in Sudan?

Sudan is experiencing one of the worst humanitarian crises in recent times due to three years of conflict. The conflict has displaced 14 million people, with nearly half of the country facing acute hunger. Over 18 million people require urgent medical help for injuries and disease. Aid groups have accused the parties to the conflict, the army and paramilitary Rapid Support Forces, of using sexual violence as a weapon of war. The prospect of negotiations to stop the fighting appears dim.