Which is exactly where the system went wrong, and the political parties (which, I remind every one are not - repeat - not part of our political system, but private entities seeking power through elections) usurped the power of Parliament: All MP not otherwise in government (meaning members of the council of ministers) are there to hold government to account on behalf of their riding's constituents.
If all Members of Parliament not otherwise PM, Ministers or Ministers without portfolios remembered that, our system would work so much better. Unfortunately, political parties (all of them) and the government in residence (the civil service) have emasculated Parliament to the point where, in majority government, the PM is basically a dictator for four to five years.