Why would a business replace human capital with physical captain

A business would replace human capital with physical capital to achieve economies of scale.

Explanation:

Economies of scale are cost advantages obtain when there is an increase in the output of the operation. As production rises there is more efficient to use robots or machinery than humans to produce any given product.  The use of this machinery will need a big investment but in the long run the costs of production will decrease and there is easier to manage machines than humans.

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