I agree . In short, I think he'd had a gut full.
A gut full of what? Being a hopeless PM?
He was fired by the party, "thanks for doing the job, but we don't want you anymore, please move aside", like he did to Abbott. Note MT was well reknown for being the ongoing leak in the camp, spent his entire time when not being PM trying to undercut Abbott, was probably one of the most disloyal senior ministers there ever was to his own leader.
Abbott at least gave MT a decent job, (which he screwed up).
Gillard gave Rudd a decent job to keep him busy.
Turnbull sent Abbott to the back bench with nothing to do. MT's treatment of Abbott in the weeks following the dumping was heavily critised by many, even those in the ALP and MT had plenty of time to fix the issue, he didn't. He took the job off TA because he was loosing popularity and making a number of very public gafs. He's too young to retire and a career MP with no significant previous private sector career, so what do you think he will do, just resign? Should TA have resigned from the house at the previous election, probably, however MT would still have been dumped as he is one of the worst PM's we have had in recent times. Not sure if he's worse than Gillard, but up there. At least she could make a decision. Yes, TAs should have shown more loyalty.
When Gillard was being challenged by Rudd for the final time, she had the respect to at least say, "who every looses walks away quietly and retire from politics to walk away after the next election". After being dumped, she did the respectful thing and advised the party and house a few weeks after being dumped she was not contesting the seat. Gillard's main issue was her back flipping on the CO2 tax for which the marginal electorate never forgave her for.
Hawke did the same, was fired after years of having Keating on his heels and finally winning. Went to the back bench quietly for a while then resigned from the house.
What Rudd, Gillard and Hawke never did was risk their parties position to hold office!
MT had a gut full alright, but it was all his doing and nothing more than he did to TA and it continues in his "take my bat and ball and go home if I don't keep the PM's job" attitude. He was pi$$ed off from the start when he lost by one vote to TA as opposition leader, went after TA ever since and when he finally got the top job, he screwed it up! By his own admission, loosing 30 public opinion polls in a row is not a sign of something doing a good job. He hasn't just hurt the LNP, he's cost the taxpayer and likely going to cost a lot more in an early election and political instability.
MT should be kicked out of the LNP party for his actions, which probably suits him fine as he never wanted to be in the LNP in the first place, he wanted ALP. However he will likely go down as one of the better PM's ALP should have had, at least he improved the budget situation, something no ALP PM's have managed to do since Hawke.