History of parliamentary leadership accountability

The Guardian reports that New Zealand's opposition Labour Party, facing an election and low in the polls, made a smooth, efficient, and legitimate leadership change the other day, with Andrew Little stepping down and MP Jacinta Ardern being selected unanimously by Labour's parliamentary caucus to succeed him, all in the course of a single caucus meeting,  The leadership change took no time, cost no money, and ensured that the new leader of the party actually had the support of the elected Labour Party representatives of the people, and would remain accountable to them -- even as prime minister,

Compare the long, slow, expensive, ethically dubious vote buying lollapalloozas Canadian federal and provincial parties have been engaging in lately.

The Labour MPs chose a 37 year old woman to lead them.  But New Zealand is not entirely enlightened.  Talk show hosts immediately began grilling her as to whether being party leader or prime minister would interfere with her opportunities for parenthood.

Update, August 9:  In the week+ since the parliamentary Labour caucus made this change, Labour had risen in the polls from 24% to 33% and Ardern is even with Prime Minister Bill English in voter preferences.