A single, more powerful party can shape the policies of the coalition disproportionately. Smaller or less powerful parties can be intimidated to not openly disagree. In order to maintain the coalition, they would have to vote against their own party's platform in the parliament. If they do not, the party has to leave the government and loses executive power. However, this is contradicted by the "kingmaker" factor mentioned above.
A single more powerful party can shape the policies of the coalition disproportionately Smaller or less powerful parties can be intimidated to not openly disagree In order to maintain the coalition they would have to vote against their own party's platform in the parliament If they do not the party has to leave the government and loses executive power However this is contradicted by the "kingmaker" factor mentioned above