when one member of a society owns all of the goods, and redistribution of items cannot take location barring making that member worse off, the society can be said to be Pareto efficiency.
Pareto efficiency, or Pareto optimality, is an financial kingdom where assets can't be reallocated to make one person better off except making at least one person worse off.
Consider some other example: the sale of a used car. The seller can also price the car at $10,000, while the customer is willing to pay $15,000 for it. A deal in which the car is sold for $12,500 would be Pareto efficient because each the seller and the client are better off as a end result of the trade.
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