Constitutionally we do not elect the “Prime Minister” but modern day electioneering tends to the view that people think they do. It can reasonably be said that those who vote for a major party take into serious account who the Prime Minister of that party will be. In practical terms it can be called the people’s choice.
The period after an election is usually known as a “Honeymoon” for the new government and leader.
Then usually a period occurs where policy is implemented that may not be “populist”. It will usually be a period where the nearly 50% who did not vote for the party in power will have the greatest opportunity to attack the implementation of policies, and the derivatives of those policies, which they always opposed.
Government is then forced by looming elections to turn to more popular strategies and hopefully deliver the benefit of the hard choices. The people then decide again for the next three years.
I do not particularly support the current PM but it seems to me that changing PM after only 18 months is not going to help Australia.
If the people decide at the next election, which is only 18 months away, that they don’t want him, and he loses, then and only then should party power players change their horse. 18 months is not a fair go for a man who has so long been in politics and who is almost certainly following a three year plan .