Tony Abbott has a memorable way of talking about himself as a dog.

Years ago when he entered parliament he told the world he was keen to be a “junkyard dog savaging the other side”.

He was, magnificently.

He talked dogs again while in exile on the backbench after the downfall of the Howard government. He warned ambitious politicians of finding themselves, “like the dog who catches the car. What do you do when you finally get that great office for which you have striven all these years?”

This week is proof positive that he never really found an answer to that question. True, there are things he wants to do, backers he has to satisfy and promises he has to keep. But when his survival depended on convincing Australians he was the leader for them, he delivered stump speeches about little more than averting economic catastrophe and dealing with terrorists.

Yes, of course. But what about the rest?

The failure which may carry Abbott out of public life on Tuesday is his failure to grow. In thoughtful interviews over many years he claimed to be so much more than the savage dog of his party. There were values, deep values waiting to be expressed once he had the chance to lead.

Twenty years of political brawling in Canberra didn’t touch Abbott’s romantic notion that he would grow once he had power. From childhood his heroes had been men like Churchill who transformed themselves when they came to office.

In the belief this would happen, a chunk of the electorate was willing to vote for this startlingly limited man in 2013. They took him at his word: that he would be able to dig down to his better self and be the leader the nation needed.

But it didn’t happen.

The junkyard dog united a shattered Coalition and proved himself the most resourceful leader of an opposition in 50 years. But no transformation followed. The prime minister’s problem is not the captain’s picks, not his failure to consult, nor the micromanagement of the cabinet by his office. He failed to grow.

That’s what made his quixotic knighting of the Duke of Edinburgh so devastating. It was not just the act of a leader more alert to the romance of the crown than the feelings of his country. It was so un-grown up.

Abbott is not the brawling kid he was at university. Life and politics have taught him a great deal since then. But to an uncomfortable degree he remains the man recruited in his teens by the conservative fanatic BA Santamaria to save the nation from the future.

Stopping things became his forte: stopping student radicals, stopping the republic, stopping Pauline Hanson, stopping Rudd and Gillard, stopping the boats. He is very good at it. His greatest boast at the Press Club was the list of all he had stopped.

And what’s it all for?

Pundits reckon he needs to find a narrative for his government. He has that. As he has said so often since the night he was elected, Australia is open for business again. That’s the story. But that isn’t winning Abbott the nation’s regard.

Deeper than policy is the problem of him. What he needs to survive now – if the numbers haven’t already moved against him – are the bigger sympathies of a leader able to speak, an adult to adults, about the country he leads.

And if he can’t, the dog metaphors are too grim to contemplate.