Why did the liberum veto weaken the Polish-Lithuanian Commonwealth?

The liberum veto significantly weakened the Polish-Lithuanian Commonwealth by mandating that all legislation in the Sejm be passed unanimously. Based on the principle of absolute political equality among the nobility, any single deputy could nullify a measure or dissolve the entire legislative session by exclaiming "Nie pozwalam!" ("I disapprove!").12

This mechanism crippled the state in several ways:

• Governmental Paralysis: The veto was used so recklessly that it frequently brought government business to a standstill, making the centralization of power impossible.12
• Foreign Interference: The system left the Commonwealth highly vulnerable to foreign powers. Ambassadors and powerful magnates routinely bribed individual delegates to exercise the veto, effectively sabotaging any legislation that threatened their interests.12
• Constitutional Instability: Because a veto could dissolve a session, all previously passed acts were nullified and required resubmission, preventing long-term political stability.12

These systemic flaws persisted until the Constitution of May 3, 1791, finally abolished the practice in an attempt to reform the failing state.1