Why are governments unstable in nations with multiparty systems?

Coalitions often break down when disputes arise

Explanation:

A coalition government is a form of government in which two or more political parties often combine to obtain a majority and form a government. The usual reason for this arrangement is that one party rarely gets enough support to control the government.

However, coalitions often break down when disputes arise.

So, governments is unstable in nations with multiparty systems.