She did the best with what she had

The Reserve Bank's building in central Pretoria looks like something out of a Stephen King novel, a young colleague remarked recently.

"It's so tall ... and evil," he said as he accompanied me to the announcement of the interest rate decision two months ago.

"The sort of place from where millions of lives can be controlled," he mused.

Departing governor Gill Marcus is not evil but she probably wishes she possessed some of the magic from King's stories.

You can't confine the consumers of an entire country under a dome. Not with the few instruments Marcus has had at her disposal. She has instead tried harder to lift the invisible dome trapping our debt-laden people.

Marcus cut interest rates three times in her first year at the helm, lowering the repo rate (and prime) to its lowest in four decades. She paused for 20 months before slashing it further in July 2012.

South Africa's economic growth prospects were feeble and, despite inflation being closer to the ceiling (6%) of the Reserve Bank's target band than the floor (3%), the repo rate was cut to 5% and prime to 8.5%.

She was concerned at the time that Europe's weak growth and sovereign debt problems would damage growth here. She wanted cheap money to help "the fragile domestic private-sector investment and consumption trends".

Little did she know that South Africa would within weeks start taking control of its own destiny in a very destructive way with the Marikana massacre.

In the months that followed she warned against the instability in mining and the "protracted" unprotected strikes she said had the "potential to undermine already fragile private-sector investment sentiment".

It did. Consistently, from the end of that year - and again last week - the Reserve Bank has down-scaled its economic growth forecasts.

Weeks before Marikana, Marcus and her team still expected GDP growth of 4.1% for this year. Now they forecast 1.5%, with risks that it might be even lower.

Throughout her tenure as the head of national monetary policy, inflation has hugged the upper limit of the Bank's target band.

It is not really her fault. Most analysts say she has done a good job over the past five years.

But Marikana's tail - and the US Federal Reserve's reversal of quantitative easing - has weakened the rand to levels difficult to imagine two years ago. The result has been higher inflation.

For the past five months it has been above the Bank's upper threshold and is not expected to fall back below 6% before Marcus leaves Madiba Street.

She has had to raise rates twice this year and they will most likely have to go up again soon.

People who have attended her interest rate announcements will miss her courtesy and clarity, especially those who remember the outbursts of her predecessor, Tito Mboweni, and his cringeworthy sense of humour.

Marcus did what she could with what she had.

But the Reserve Bank, she has warned (not in those exact words) is not a magical place. Monetary policy can only do so much. Although growth has seemed to feature much more in her thinking than in Mboweni's, keeping inflation under control has always been her real mandate.

But growth is up to us: consumers, unions, business and the government.