Pay for performance only works if the marginal value of pay is greater than the marginal cost of performance. A performance bonus of $6.40 per week is less than

Pay for performance only works if the marginal value of pay is greater than the marginal cost of performance. A performance bonus of $6.40 per week is less than a third of that pay at 40 hours, so why would someone work more than an additional 20-40 minutes (depending on time usually spent at work) to obtain it? Evidence is that the value of their time is around $20 an hour, after all.