What the system does is the rostering system preferences the workers with the highest scores when assigning shifts. And I suppose makes this number viewable to the workers so they can see why they have to optimise.
The supply of even untrained workers is finite, so you have to treat them as people.
We could do this with developers too. Give the biggest raise to the developers with the most lines of code committed, and maybe design a shiny dashboard with it as a number to replace the project manager. What could possibly go wrong?