Tony Abbott was warned years ago to be wary of Mal Brough. Like most good advice, he ignored it.
Brough, the former Howard government minister who lost his Queensland seat of Longman in 2007, was angling for preselection in the adjacent seat of Fisher ahead of the 2013 election.
It was a no-lose option for whoever in the Coalition won preselection, as the seat was held by Peter Slipper.
Brough was never that popular among colleagues under Howard, if only because he was ambitious, did not lack self-confidence and was being rapidly promoted.
Abbott, as Opposition leader, was counselled by some of his shadow ministers to try to veto Brough's preselection.
"The only job he wants is yours," Abbott was told.
Brough has no chance or intention –yet – of becoming leader, but should Abbott fall next week or soon after, Brough would have played a significant role and will have his hand out for a return to the ministry.
Leadership spills always begin with those Paul Keating once dubbed the "low-altitude flyers". Those with either no talent or those like Brough, with nothing to lose under the current leader, are almost always the first to throw the bombs.
Malcolm Turnbull's first stint as Liberal leader was brought undone to a large degree by his inability to think like a politician rather than a businessman. In business, pernorkles don't count. In politics, everyone has one vote each. To his peril, Turnbull ignored and disparaged the likes of Wilson Tuckey and Dennis Jensen, who would bag him daily, on behalf of a great many others, over his determination to have the party accept a price on carbon.
Ironically, Jensen, a scientist who was outraged when Abbott initially refused to appoint a science minister, joined Brough as one of the first bomb-throwers against Abbott.
Brough's sudden interest in health policy this week, followed by a press conference in which he pulled his unconditional support for Abbott, helped set the ball rolling.
Ultimately, however, if, or when, Abbott is deposed, he will have no one or no thing to blame but himself.
Since winning the election, he has operated under the assumption that the unholy mess that befell Labor after Kevin Rudd was dumped as prime minister would shield him from any challenge. It was a fair assumption and one the political establishment, this column included, supported.
But, as one MP said before Christmas when the first serious whisperings began, "politics has changed".
If Abbott is dumped this week or soon after, it will mean that at a federal level, there has been a change of leader or attempted change in either the Labor or Liberal Party every year since 2003 except for 2004, 2011 and 2014. That's nine changes and two attempts in 13 years.
Colleagues of Abbott say he is shattered at how quickly things have deteriorated. It took him some days to comprehend the enormity of the damage caused by his Prince Philip brain fart.
What will really gall him is that if he is tossed after just 16 months in the job, he would have held office for a shorter time than either Rudd or Julia Gillard, both of whom he cannot abide.
Gillard had her flaws as leader but she also had it a lot harder than Abbott. Gillard and her colleagues were savaged daily by the News Corp tabloids and the shock jocks, they were opposed by the powerful lobbies representing business, mining, energy and gambling, and she was being actively undermined by Rudd and his supporters. Abbott was undermined by nobody and News Corp and the lobby groups were on his side. This is his work.
His demise has little to do with not promoting the malcontents. Had the polls stayed healthy, they would be silent or ignored. His fortunes plunged in May last year when he broke his compact with the voters with a budget full of broken promises. After winning an election on trust, honesty and no surprises, he not only betrayed all that, but he treated the voters like dunderheads by telling them he had not broken promises.
"Many people woke up on the Wednesday morning after the budget and found two very big packages looking to provide a solution to problems that they weren't aware that we had," said Andrew Robb on Thursday.
"We didn't carry out the process; it's hung around our neck ever since and it's overwhelmed and shadowed all of the major achievements that we had throughout the year."
Any chance he had of rebounding was hampered by Abbott's stubborn refusal to listen. He refused to dump his paid parental leave scheme – a policy that angered the base and destroyed the budget narrative – until it was way too late. He refused to dilute the enormous power wielded by his chief of staff, Peta Credlin, and even when it was apparent he was in deep trouble, he chose to amend and persist with controversial budget policies on Medicare and higher education, rather than dump them.
In the end, a stupid but innocuous decision to make a prince a knight brought him unstuck. It was his Karl Rove moment.
If, as is increasingly likely, Abbott is supplanted by Turnbull, the new leader, too, will be on notice. Already, the Nationals and unnamed MPs have expressed that they will only accept Turnbull should he not lurch too far to the left. No emissions trading scheme, no gay marriage, no republic.
Already, old enmities are starting to surface from the turbulent year of his leadership.
"Who for deputy? Godwin Grech," texted one Liberal who clearly harbours misgivings abut a change.
Turnbull, one assumes, has learned from his earlier errors and he can visit his moderate policy agenda much later should he be able to consolidate his leadership and win an election in his own right. His immediate priority will be the economy.
Abbott and Hockey are deemed by the Liberal Party base unable to fix the budget because they are unable to bring the people with them.
It was the base – business, the big donors and so forth – that led the push for a leadership change, not the media or the left. This has not been a push to install the alternative government but to install a a leader who will stop Labor regaining government.