I think you underestimate the motivating power of self-respect.

I heard a story of a failing auto factory and one of the things they did to fix it is they started a "bring your family to work" day. The workers were encouraged to clean up their work space and to add personal effects to make it their own, so that when their families came to see it, they had a sense of pride about their job.

They also encouraged inter-departmental competitions and monetary incentives, so I'm not trying to suggest that isn't an important factor in motivating people. I'm suggesting that there is more to motivating people than money.

Most of the people I've worked with in life do not want shares in the company or a variable income in any way. They want a secure paycheck which has - above all else - predictability. People raising families don't want to worry that they may not earn enough to feed their families if their coworkers decide to slack off for a while.