LEIGH SALES, PRESENTER: As I mentioned earlier, it's been a very rough couple of days for Tony Abbott.
For a man considered one of the most effective opposition leaders in Australian history, the speed of his collapse as prime minister has been astonishing.
He did meet two of his most substantial election promises - stopping the boats and axing the carbon tax - but his failures overshadowed that.
Hayden Cooper takes a look at the causes of Tony Abbott's demise.
(Footage of Tony Abbott at Liberal Party election headquarters, Four Seasons Hotel, Sydney, 7 September 2013)
ELECTION ROOM SUPPORTERS (Sep. 2013): Tony! Tony! Tony!
HAYDEN COOPER, REPORTER: Tony Abbott in happier times: election night 2013.
He promised a government of no surprises, but few here could have predicted what was to come: a reign even shorter than the two warring Labor leaders he'd replaced.
TONY ABBOTT, PRIME MINISTER 2013-15 (Sep. 2013): It is the people of Australia who determine the government and the prime ministership of this country. And you will punish anyone who takes you for granted. And that's as it should be in a great democracy such as ours.
HAYDEN COOPER: In the crowd, the new prime minister's sister: Christine Forster, a Sydney City councillor. Now, just shy of two years on, she's as shocked as anyone.
TONY ABBOTT (Sep. 2013): Thank you so much.
(Applause and cheers)
CHRISTINE FORSTER, TONY ABBOTT'S SISTER: My brother is a man of great honour and integrity, dedication. He'd worked most of his life to win the prime ministership. He valued it very highly. He was dedicated to the service of his country.
So, you know, I'm sure he will be absolutely devastated by what's transpired. He'd won a resounding election victory in 2013 and it's my view that he very much deserved to see out a full term. Unfortunately, that's not now happened and the party's made a decision.
HAYDEN COOPER: His early achievements followed the course of his election campaign mantras on refugees and the carbon tax.
TONY ABBOTT: If you elect the Coalition, you'll stop the big new taxes and you'll stop the boats.
CHRISTINE FORSTER: Tony really has achieved pretty much everything that he said that he would. He stopped the boats. He's abolished the carbon and the mining tax. They were working hard to start to get the budget back under control. You know, they are significant achievements and a great legacy.
TERRY BARNES, FORMER ADVISER: These are going to be very significant achievements that he can look back on with pride. It made him unpopular, there's no question, but he did what he thought was right.
JOE HOCKEY, TREASURER (May 2014): I commend the bill to the House.
LOWER HOUSE MEMBERS (May 2014): Hear, hear. (Applause)
HAYDEN COOPER: The trouble for Tony Abbott's government began at budget 2014, a harsh cost-cutting document that cut welfare for families, pensioners and the poor.
(Footage of Joe Hockey and Matthias Cormann smoking cigars)
HAYDEN COOPER: This image didn't help.
TERRY BARNES: It was a tough budget to put together. It was a tough budget to sell and they ran up against very heavy headwinds, Tony Abbott and Joe Hockey, and they struggled.
HAYDEN COOPER: Along the way, the prime minister took a hard line on the downing of MH17...
TONY ABBOTT (Oct. 2013): Look, I'm going to shirt-front Mr Putin. Ah, you bet you are. You bet I am.
HAYDEN COOPER: and made the Islamic State his favourite talking point.
TONY ABBOTT (Oct. 2013): This death cult wants to kill.
HAYDEN COOPER: But missteps would irritate his colleagues and voters, like his response when questioned on what he achieved as Minister for Women...
TONY ABBOTT (Dec. 2014): As many of us know, women are particularly focused on the household budget and the repeal of the carbon tax means a $550 a year benefit for the average family.
HAYDEN COOPER: refusing to help Burmese Rohingya refugees stranded at sea...
TONY ABBOTT (May 2015): Nope, nope, nope.
HAYDEN COOPER: and, perhaps above all, granting a knighthood to Prince Philip, the Duke of Edinburgh.
REPORTER (Jan. 2015): This is a captain's pick?
TONY ABBOTT (Jan. 2014): Look, I'm not going to dispute your characterisation.
HAYDEN COOPER: Twelve days later, he fought off a move to replace him and promised a new start.
TONY ABBOTT (Feb. 2014): Good Government starts today.
HAYDEN COOPER: But polling didn't improve and other scandals soon emerged to make matters worse.
Terry Barnes is a former Abbott adviser:
TERRY BARNES: There are many things that went wrong for the Government, there's no question. And certainly the last couple of months, particularly since Bronwyn Bishop's helicopter controversy came into the news, have not been very good for either the Government or for Tony Abbott as the prime minister - and ultimately that has cost.
HAYDEN COOPER: What we don't know is what's next for Tony Abbott. Will the career politician continue or call it a day? He's yet to reveal his plans.
CHRISTINE FORSTER: Oh, look, I'm sure he's devastated. But, you know, he's been in politics a long time and he knows that politics is a brutal game. And I'm sure, like me, feeling very sad about what's happened but he will come back stronger, I'm sure, and better because he's got a great track record of doing that.
LEIGH SALES: Hayden Cooper reporting.