Another example of a command economy is a dictatorship, like in the case of Hitler during WWII. In command economies, GDP and HDI tends to be much lower than in market or mixed economies. This is caused becuase of lack of support from the people, or in communism's case the lack of need to work, since you'll be brining home the same income anyways. In countries like these, the state purely decides the production of goods and how much each sells for and in essence, owns everything. Countries which are still command include: North Korea and Cuba.
Via Kevin Shao