What are the disadvantages of a coalition?

Answer 1

Theorists who disapprove of coalition governments believe that such governments have a tendency to be fractious and prone to disharmony. This is because coalitions would necessarily include different parties with differing beliefs and who, therefore, may not always agree on the correct path for governmental policy. Sometimes the results of an election are such that the coalitions which are mathematically most probable are ideologically unfeasible, such as in Flanders or Northern Ireland. A second difficulty might be the ability of minor parties to play "kingmaker" and, particularly in close elections, gain far more for their support than their vote would otherwise indicate. Additionally, existing, powerful parties can use their leverage in coalition to hinder the growth and formation of new parties by forming alliances without them.