For draining deep mines, what was the initial crucial advantage of Newcomen's atmospheric engine, overriding its inefficiency?

Answer

Operational security and predictability in pumping water

In mines susceptible to flooding, the primary value of Newcomen's engine was its guaranteed, steady pumping action, which provided a level of reliability that variable river levels could not match, enabling deeper digging.

For draining deep mines, what was the initial crucial advantage of Newcomen's atmospheric engine, overriding its inefficiency?
inventionmachinepoweradvantagesteam engine