FirebrandRoaring: https://www.nytimes.com/2017/09/03/upshot/to-understand-rising-inequality-consider-the-janitors-at-two-top-companies-then-and-now.html
In the 35 years between their jobs as janitors, corporations across America have flocked to a new management theory: Focus on core competence and outsource the rest. The approach has made companies more nimble and more productive, and delivered huge profits for shareholders. It has also fueled inequality and helps explain why many working-class Americans are struggling even in an ostensibly healthy economy.