> One of the many fallacies here that hasn't already been pointed out is that it's impossible to determine the exact amount of revenue a single employee is responsible for in any real world employment situation.

Sure. But if it costs $100/hr in labor to run a McDonalds (split between cashier, burger flipper, fry guy), $100/hr in ingredients, and the store only produces $150/hr in revenue, it's not hard to figure out that those wages are unsustainable.

Blah blah, businesses don't deserve to exist if they can't pay whatever wage. Sure, but I'm not saying McDonalds deserves to exist--I'm saying those people won't have jobs when it becomes very obvious that the store is losing money.

Just because you can't pinpoint the exact contribution of every worker does not mean that you can't have a pretty good estimate of the contribution from retail workers in practice.

In most cases, and almost certainly in any minimum wage case, sure.

But sales people have a pretty directly attributable profit contribution.

That's true, and there's going to be a spectrum of measurement, from very measurable roles to roles that are almost impossible to measure. I'd say even in the sales case, something that isn't getting measured is how much a good salesperson can rely on other parts of the organization to answer questions for customers that can make the difference in landing the sale or not. That attribution usually goes entirely to the salesperson, when someone else's knowledge was key to the transaction. It's a team effort.

This is most obvious when you take the extreme case of looking at the department level - sales and marketing are "responsible" for 100% of the revenue, but if you delete legal, support, R&D, HR, and finance, your revenue goes to zero pretty quickly.

So what, an employer is gonna go on losing money and will never look into why? If they go out of business then the employee will also lose their job.

If the aggregate across all employees is negative, the company is losing money. If the aggregate over all employees is positive, you have profit.

It's like that old joke about marketing budgets: half is wasted, but it's impossible to tell which half. The same can be true for employees, maybe half your employees lose money, but the other half make enough that you're profitable, but you can't attribute every dollar that comes into your company to the specific employee that generated that dollar.