A prudential reason for power sharing is that it leads to an avoidance of conflict between social groups. Since social conflict often leads to violence and political instability, power sharing is a good way to ensure the stability of political order. In India, seats have been reserved in legislatures for the socially weaker sections keeping in mind this prudential reason for power sharing.
A moral reason for power sharing is that it upholds the spirit of democracy. In a truly democratic setup, the citizens too have a stake in governance. In India, the citizens can come together to debate and criticise the policies and decisions of the government. This in turn puts pressure on the government to rethink its policies and reconsider its decisions. This active political participation is in keeping with the moral reason for power sharing.