The most effective person gets hired into a role. The firm performs well, moves more product, lowers prices for customers, sends larger orders to its suppliers,

The most effective person gets hired into a role. The firm performs well, moves more product, lowers prices for customers, sends larger orders to its suppliers, invests some surplus in R&D, grows its payroll, generates return for shareholders who then invest their gains in other enterprises, etc. Or an ineffective person is hired and the opposite happens. https://en.m.wikipedia.org/wiki/Lump_of_labour_fallacy https://en.m.wikipedia.org/wiki/Lump_of_labour_fallacy