The pursuit of efficiency often produces myopia. If efficiency is the rate at which we turn "what we have" into "what we want," then we first need to know what we want.
When processes are "efficient", they tend to be efficient with respect to a single variable--the thing we purportedly want. Sometimes we want more than one thing, though. When multiple variables are thrown into the mix, tradeoffs and value judgments necessarily come into play.
A daycare might have low cost-per-student (lower cost) or just a few children-per-teacher (better care), ...
Note: This isn't to say that efficiency is meaningless when optimizing for multiple variables. A low cost daycare with excellent care is obviously more "efficient" in every sense than the crappy, expensive daycare. It's just that when multiple variables come into play, people want to be "holistic" rather than "efficient" in the sense that they want to consider and weight numerous important variables.