In any transaction the buyer and seller compete to buy cheap and sell dear. For one to get more, the other must get less. Those affected by the transaction but not directly involved as buyer or seller have no say in it. Even with markets working optimally, actors become individualist. Their motives and preference development are skewed toward me firstism.
Exchange rates ignore social and external effects and therefore diverge from true social costs.
And a class division emerges between those few who monopolize decision-making skills, opportunities, and information, and a much larger group disempowered and disenfranchised from decision making. The former we call coordinators. They rule the economy. The latter are the workers. They follow orders.