How is that?

The easiest business metric for measurement is profit per worker hour. What do you mean, "How is that?"

I asked "How is that?" because relying on worker-reported hours is no less consistent with the profit motive than are current standards for salaried employees.

Employers can still calculate "profit per worker hour". And it's arguably more accurate when based on reported work time, rather than just days worked.

It's also relatively useless as a measurement, so you'd expect the profit motive to drive people away from it.

> It's also relatively useless as a measurement

It is not. It's specifically used because of the utility in the simplest tasks. Factories are designed around throughput and efficiency of workers.

What would you do with it in an office, though? It's well known that you can't just throw man-hours at cognitive tasks and expect linear or even monotonic returns.

Fair enough. I was mostly talking about professional staff, such as engineers, and some trades. Most traditionally, for example, lawyers and plumbers.