Step 1: Start from what happens without power sharing.
When one group or one person holds all the power, other groups feel ignored, which breeds resentment and can eventually lead to conflict or even the breakup of a country.
Step 2: Explain the prudential reason.
Sharing power among regions, communities, and institutions reduces the chances of conflict because every group gets a stake in the system and feels heard, which keeps the country stable and peaceful.
Step 3: Explain the moral reason.
Beyond just avoiding conflict, power sharing is simply the right thing to do in a democracy, since people have a natural right to be consulted and to have a say in decisions that affect their own lives.
Step 4: Bring both reasons together.
So power sharing is necessary both because it keeps a diverse society stable and because it reflects the basic democratic idea that everyone deserves a voice, which together make it essential for any healthy democracy.