Why are prime ministers often weaker in coalition governments?

Prime ministers in coalition governments are often considered weaker because they must balance the competing interests of multiple political parties to maintain a legislative majority. Unlike leaders in single-party majority systems, these prime ministers face several constraints that limit their authority:1

• Cabinet Appointments: The prime minister must distribute ministerial roles among coalition partners to ensure their continued support, often leaving them with little influence over who fills specific positions.1
• Policy Control: With power shared across parties, the prime minister may struggle to exert firm control over policy direction and may be forced to make executive decisions through consensus rather than unilateral action.1
• Legislative Timetable: The prime minister often lacks direct control over the legislative agenda, as they must negotiate with partners to keep the government functioning.1
• Departmental Independence: In these systems, department heads—particularly those in finance or foreign affairs—often possess more independent control over their ministries and maintain their own followings within the legislature.1

Ultimately, these prime ministers may be reduced to a "first among equals" role, chairing discussions rather than acting as a powerful chief executive.1