The usual practice is for the newly-deposed PM (whether thrown out of office by the voters or by his/her party colleagues) to give a dignified press conference outside parliament house where they thank the Australian public for the great honour of leading them.

The ex-prime minister then vows to take some time away from the gaze of public scrutiny to reconnect with their family while they consider their future and whether they intend to stay in parliament.

Nowhere do they vow to remain just on the periphery of the political scene, occasionally throwing pot shots at their predecessor in a bid to undermine their leadership and cast their own time in power in a better light.

But, more often than not, that’s exactly what happens.

The latest to go down this path is also the latest prime minister to be deposed.

Malcolm Turnbull might claim he did not expect his description of Tony Abbott and Kevin Rudd hanging around like “miserable ghosts” to find its way into the public domain, but nor he would he have been surprised that it did.

He may have made the remarks during a private function but when every telephone doubles as an audio and video recorder, modern politicians know that Chatham House Rules no longer carry any weight.

Ironically, Mr Turnbull was actually saying he intended to get well out of politics now he has left The Lodge, but those very remarks dragged him straight back in.

But why? There are probably a number of reasons why so many ex-PMs find it so hard to walk away, but a sense of unfinished business seems to be a common thread.

Indeed, the two ex-PMs that have probably best transitioned to a life outside politics – Bob Hawke and John Howard – are the two longest-serving PMs of the past 30 years, and the two most successful.

Neither left The Lodge on their own terms, but both left behind a legacy of great achievement while they were there.

Perhaps satisfaction with their time as prime minister has allowed both men to effectively walk away from politics when their time was up.

What then, does that say of the performance of those who just cannot seem to let go? By hanging around, they answer that question themselves.