Question

what are the advantages and disadvantages of a coalition government

Answer 1

Advantages
1. Consensus or majority based decision are taken considerings views of every party .
2. Regional aspirations are fulfilled or considered.
3. Favours nationalism and lowers regionalism.
4. Lowers tyranny of government.
5. More responsible government

Disadvantages
1. Unstable government
2. Time consuming process of decision making .
3. Sometimes National interest is kept aside for accomplishing regional interest. Happened when UPA government was in centre it didnt concluded water sharing agreement with Bangladesh because West Bengal regional party was of the veiw that it will hamper WB development.
4. Generally appeasement policies are considered rather developmental policy

hope this answer helps you

Answer 2

Advantages: You get a stronger government with a majority coalition than a party trying to rule with a minority. More people's views are represented in the policies implemented than if just one party ruled. Potentially a stronger/more talented team leading the government, as the PM can then chose the talent from two parties, rather than just his own.
Disadvantages: Less stable, a coalition is more likely to fall apart and break up than a one-party government. It is less accountable - who do you hold responsible for mistakes at the next election if there is more than one party in the government? Politicians can easily just say 'it wasn't us, it was the Liberals' or whatever, reducing their accountability to both Parliament and the electorate. One could also argue that they are less democratic - no one voted for a coalition, and as some of the policies of every party involved will have to be dropped in the compromise, even those who voted for one of the coalition parties are not getting all the policies/ideas they voted for.