On the face of it, Glenn Stevens leaves his last monetary policy meeting with an enviable record.

The central bank boss who — in the midst of the deepest global downturn since the Great Depression — presided over a continuous period of economic prosperity.

The unemployment rate has mostly had a "5" in front of it — a "4" at times — since he took over in 2006, after averaging almost 6.5 per cent over the previous ten years.

Headline inflation has averaged 2.3 per cent a year during his ten years at the helm and the underlying inflation rate, 2.7 per cent: both within the Reserve Bank's target range of 2 to 3 per cent over the cycle.

Although the pace of growth has slowed, Australia has avoided a formal recession and not experienced any lasting downturn during his reign.

But it could easily have been otherwise.

Although his tenure coincided with turbulent times for the global economy, the 12th governor of Australia's central bank has enjoyed a deal of good luck; ironically, that global financial turmoil may have saved the nation, and the RBA, from a domestic economic crisis.

Cast your mind back to 2008.

With the Australian economy running red hot, the consumer price index hit a high of 5 per cent.

Last month, when Stevens gave an account of his record, he effectively conceded that the central bank had lost control of inflation.

"The bank's analysis at the time was that the economy was overheating and inflation was rising mainly for that reason. That judgement stands the test of time. "The marked change in the path of the global economy in 2008 had a big effect on sentiment in Australia and the course of the economy and prices. Absent that, I suspect we may have had a fair bit more trouble containing inflation."

As it was, the RBA had pushed the cash rate up so far by 2008 that variable mortgage rates were just shy of double digits.

Absent the global crisis, the RBA would have been forced to ratchet up interest rates even further to contain an inflation breakout.

Could the stress on highly indebted households have caused a home-grown recession?

At the time, the Reserve Bank steadfastly denied there was a problem with household debt levels.

Yet, secret research carried out at the time by the banking regulator suggested otherwise.

There is a strong argument that the onset of the global crisis averted a boom-bust cycle in Australia, and a possible banking crisis, as rising interest rates hit households who had been allowed to borrow excessively as the Australian banks lowered their landing standards.

Australians carry unprecedented debt burden

Mortgage debt levels have doubled since then. On just about every measure, Australians are carrying an unprecedented household debt burden, unparalleled in the world —125 per cent of GDP.

In his exit speech, Glenn Stevens commented on the focus on government debt while concerns about private debt are overlooked.

"Popular debate in Australia about government debt and how we limit or reduce it seems so often to be conducted while largely ignoring the size of private debt. "To outside observers this seems odd. Foreign visitors to the Reserve Bank over the years have tended to raise questions about household debt much more frequently than they have raised questions about government debt. "So the way ahead is going to have to involve a rather more nuanced consideration of all these issues."

The irony is that the central bank has facilitated the latest rise in household debt levels by driving interest rates to record low after record low.

Glenn Stevens has faced the dilemma confronting central bankers across the developed world: that low interest rates put in place to deal with low inflation, the threat of deflation, or tepid economic growth, run the risk of causing dangerous asset price bubbles that threaten financial stability.

He's well aware of the risks; Stevens has publicly questioned the extreme low interest rate policies being pursued by central banks overseas because of their impact on retirement savings.

He has also argued repeatedly that monetary policy has been left to shoulder too much of the burden of stimulating the economy, calling for fiscal policy to take a greater role through government investment in long run assets that can benefit the economy.

Glenn Stevens is no Alan Greenspan: the former US Federal Reserve chairman, hailed as a "maestro" in office then exposed as a bubble man, whose low interest rate policies and failure to perceive the risks being run up by banks led to the US housing market catastrophe.

But if the private debt bubble bursts and it all ends badly, it will similarly taint Mr Stevens' legacy.