There is a painful lesson for the National Party in the latest fracas over the leadership: if you promote show ponies from political nowhere straight on to the front bench, you're asking for trouble.
Don Brash clearly believes he can do Bill English's job.
Equally clearly, many of his colleagues do not - as yet.
If they were really confident Dr Brash was up to it, he would have been installed as leader by the end of this week, so wretched has been Mr English's performance.
But Dr Brash is not of a mind to get the message.
For the party's sake, he should have done one of two things. Either organised his putsch with absolute secrecy until the deed had been done. Or issued a statement at some point in the past couple of days pledging his loyalty to Mr English.
Having done neither, he leaves the party stuck in an awful limbo until the matter is resolved one way or the other at next Thursday's caucus.
Dr Brash remains finance spokesman, the second most important position in the caucus, but clearly does not support the leader.
Either Mr English goes - or he goes.
Dr Brash's ambition may be unbridled. His hurry is understandable.
At 63 he is not a young man. He does not have a lot of time in politics after his lengthy tenure as Reserve Bank Governor, and does not want to spend the limited time he has warming the Opposition benches.
Every politician is ambitious for the top job, but there are reasons why they start in Parliament on the bottom rung. It takes time to build a reservoir of political experience to reinforce any innate political judgment.
Dr Brash has neither.
Nor, judging by the polls, is he very popular with the public. After an initial flurry when he first mounted a botched challenge against Mr English back in April, he was scoring around 5 per cent as preferred prime minister.
That has since dropped to around 2 to 3 per cent - far below even Mr English's lacklustre rating.
What Dr Brash does possess is strong presentational skills, which make him a good performer in the electronic media.
The banker also carries a persona which radiates authority and credibility.
That would give him a honeymoon in the leader's job, which might lift National's poll ratings.
After that, however, his colleagues obviously feel he would struggle because of a lack of political nous, amply demonstrated by two shambolic plots against Mr English.
Still, the phones will be running hot over the weekend as the lobbying continues.
Coup plotting usually withers after exposure to sunlight because the incumbent, forewarned, can fight back by bestowing patronage on loyalists and calling in debts.
But coups are unpredictable beasts - and the environment remains rotten ripe for a leadership change.
The big danger - and the thing that must worry National MPs - is that Dr Brash as leader could take the party even lower in the polls than Mr English has succeeded in doing.
Poorly as it may be performing now, National, with Winston Peters' New Zealand First breathing down its neck, simply cannot afford to let that happen if it is to retain its near 70-year-old legacy as the major party on the right of New Zealand politics.