[ntfAX]

It might be a combination of efficiency and generating value. If you're efficient enough to generate $1000/hr but the org has no opportunity or product for you that can generate this, efficiency in performance metrics alone doesn't move the company's bottom line.

[JamesHinnek]

Exactly, the word work was used as a simplification of the overall output expected. You also need to account for the hard parts to calculate, human burnout, turnover rate, time to deliver a product to the market, amount of rework, tech debt added, etc... Someone who can deliver a fancy project, full of tech debt, will require 5x more effort on rework than was to do it, and the team gets burned out severely after the project. Would it be worth it? In the short term senior management will see it as a good idea. But most managers and senior managers are too naive to account for these hidden variables, or in most cases, not interested to take these metrics into account