When you work hourly for an employer, you are devaluing yourself. When you sign up to work 8 hours, the amount of labor that is expected of you is variable, but not in your favor. Initially you might get 1 job done in an 8 hour day but eventually you get good at your job and you finish the same job in half the time, now your employer wants two jobs done a day. Your selling point was 8 hours, regardless of your productivity, you should of got the rest of the day off and made a profit, now you got twice the workload for the same pay because your employers not gonna let you sit around the rest of the day. If you decide your going to take it easy and limit your productivity, you get replaced by the next desperate person. When you finish a job early you should be rewarded, the employer shouldn't increase their profits. If you stand up against this sort of thing, you get fired. Hold your value, draw the line.