As Adam Smith pointed out - and as we all know - there's a lot of ruin in a nation. There is not though an unlimited amount. As Zimbabwe shows us and as Venezuela is having a damn good go at proving:
There are two morals to draw from Mr Mugabe’s long, ignominious career. The first is that bad policies, corruptly implemented, can wreck a country with alarming speed and go on wrecking it long after you would have thought there was nothing left. Venezuela has little in common with Zimbabwe culturally, but has also achieved disastrous results by embracing a Latin version of Mugabenomics. By contrast, Botswana, Zimbabwe’s culturally similar but well-governed neighbour, was roughly as rich in 1980 but is now seven times richer.
We can also look at this over a longer timescale, using Angus Maddison's numbers. Roughly enough GDP per capita over history and geography was some $600 a year (these are 1992 dollars, adjusted for inflation and price differences across place). That's simply what a place without what we would call "an economy" in anything like the modern sense produces. There are indeed places out there, thankfully ever fewer of them, which have never had more than this. Those 700 million still living in these conditions tend to be - tend mind - to be some portion of a larger economy, rather than entire nations living at this level.
Except, of course, in our examples of people testing quite how much ruin there actually is in a nation. The real result of Mugabenomics, and the Bolivarian Revolution is testing that limit, is that it is possible to entirely destroy an economy, to reduce living standards to those of the Stone Age. For that's where Zimbabwe has got to, that $600 a year per head, roughly enough, in those 1992 dollars.