Those are fine points, but personal development and self respect are still incentives when the workers are also taking a slice of the profit.

I'm thinking of this is the basic sense of a factory that creates goods. The harder the employees work, the more profit the company makes. A very simple model, but also relevant to a large % of our work force. All the incentives that capitalism offers are there... personal development, promotion, self respect etc... but where employees also have a financial stake in the success of the business, well that creates a further, and extremely powerful, incentive.

Of course when we start to think of services, rather than industry, it becomes much more complicated, because it's harder to put a value on the quality of a service, as opposed the value of increased productivity. But that just takes it out of my depth.