What is the leadership based on in an oligarchy?

In an oligarchy, leadership is based on the concentration of power within a small group of individuals, often distinguished by wealth, social status, political influence, or military control. These leaders make decisions that benefit their own interests or the interests of their group, often at the expense of the broader population. The authority of this small elite typically derives from their control over resources, institutions, or strategic positions, rather than from democratic principles or popular support. As a result, oligarchies can limit political pluralism and restrict individual freedoms.