> efforts of skilled and effective people.

This has been a truism for more than 100 years and has been mocked for as long it exists. There are entire "Yes Minister" episodes about "we use the usual formula: comparison with wages of industry leaders" (they use chairmen of BP and IBM for comic effect).

Also highly recommended is the episode where Sir Arnold leaves the civil service and looks for a suitable successor who will put jobs his way ... sorry, ask him to undertake the jobs.

Excerpt:

  Sir Arnold: Also, I would like to be chairman of the
              Anglo-Caribbean Association, which would
              give me an opportunity ...

  Sir Humphrey: ... to be of service.

  Sir Arnold: Precisely, especially during the winter months.

How do you understand law firm partnerships in this wages vs capital model?

That’s a good question. I think it’s one of the few ways to convert labor to (meaningful) capital, comparable to being a founder or early employee.

The CEO of a nonprofit may be a well paid associate, but he is still just an associate. The kind of excess revenue that would flow to a partner’s profit sharing check has to be reinvested in the mission instead of disbursed to somebody in cash just because.

Does it? I know hospital system CEO’s get performance pay. Maybe if the numbers were sufficiently egregious and a newspaper (if a local one still exists) decided to do an expose the attorney general would intervene but I think in general some of these non profits are better modeled as perpetual partnerships run for the benefit of partners than they are as mission driven organizations.

Performance with respect to what goals?

Profit or close proxies for profit.