Ever since the myth took hold that John Key became popular quickly because he was not a politician - rather than despite it - others have foolishly thought they could get away with amateurism and be admired for it.
They can't. Not being able to articulate an argument under pressure matters, as former Labour leader David Shearer found out.
Saying "I don't know" to a question can be damaging, as Conservative leader Colin Craig found out on the issue of moon landings.
And saying "I stand by my views" can be extremely damaging if the issue is incest between consenting adults, as emerging politician and Act leader Jamie Whyte discovered.
He may have met some forgiveness in his party for naivety in making the original comment, but Whyte proceeded to compound the damage at the weekend by publicly explaining his error in a live television interview before his speech to the party conference in Mangere, then addressing it in his address to the faithful, and then speaking to the media after his speech where the questions broadened to polygamy.