I pay my guys "performance related", better for them, better for you. If they don`t work, they don`t get paid. If they get stuck in, they earn good money.
Once they do £120, we get half each, anything over that, they keep it. On average for a 9-5 day they earn between £60 - £100. Obviously, these figures are only a guide, it depends where you work and what you charge, but the principle still works. If at the end of the week, I`ve received my £300, then they can work Saturdays and keep all the money.
In my experience, when it`s not performance related, there`s no incentive for them to get grafting, as, they`ll get the same money regardless.