Going back to the theory of Marxist economy, they believed capitalism is inherently wasteful because the market is inherently chaotic.
They replaced it by "rational and scientific" planning of production, where production and pricing of *everything* from coal and ships to socks and toilet paper was centrally planned to avoid waste. So far, so good...
Now if you complain that this "take it or lose it" coal contract was inflexible, imagine this in the scale of the whole economy.