Arguably, the economy just is. It has no purpose, other than what it does[0].
It's not like anyone designed it, or has any control over it. Some people are in position to make adjustments, nudge some aspect of it towards a desired goal or away from undesirable one, but there's only so much they can do - it's all strongly path-dependent.
Put another way, the shape of the economy is just an exercise of descending down the gradient. Any individual or group has very little control over this, and major changes to the economy basically only happen when war or technological inventions reshape the entire gradient.
Many countries in the former soviet block would very much contradict this take.
Entire economies were indeed planned and designed, and their shape was controlled and changed at will. Individuals and groups had control, and did do major changes, including but not limited to forced resettlement and labor camps.
You can of course argue that this ended almost universally in failures, but people did try, and the amount of control over economies is very much a spectrum.
I don't disagree - in fact, this is a great study. It shows both just how much it takes to have any noticeable, direct control over the economy, and also how little it amounts to anyway.
Specifically, to have this level of control, you basically have to go full-totalitarian and rule with iron fist, and sustain this rule even as The Economy pushes back, in form of unrest, civil war, revolutions, military coups, as well as sabotage or direct attack by foreign forces. Yes, all this is part of the economy too. And, if you somehow manage to keep control in spite of all that, you'll quickly see the rest of the world, with its uncontrolled economy, zip past you in terms of wealth and power, and find yourself at its mercy.
Fundamentally, people want to trade; they both need this to survive and want it to improve their lot. If you make trade hard for them, they'll invent workarounds - alternate currencies (see e.g. use of dollar in the soviet block to work around rationing), barter, smuggling of goods; if you crack down on it, they'll conspire to depose you - and yes, even your military and security personnel, at every level, would like to make the lives of themselves and their families better too. There's only so much blood you can spill before you run out of people to kill, or out of goodwill of people doing the killing. And, as history shows, The Economy will win anyway.
As for sane, free, democratic countries - there's shit all you can do there, as the economy will push back through support of the voters and other politicians, strongly limiting the kind of decisions that are possible to implement. Try to make too big a changes, you'll get sidelined and removed from position of power.
