"We hate our supervisor. So when nobody's looking, we feed the hog."
To feed the hog means to intentionally create an unacceptable manufactured product in order to hurt one's employer. The term comes from the lumber industry, in which employees upset with their working conditions would send good lumber into the reject bin, called a hog, which is intended to shred substandard or otherwise rejected product into sawdust. This hurts the company's production, wastes raw materials, and makes the supervisor look bad to management.
This aggressive tactic of getting revenge against one's supervisors or company for perceived wrongs is fairly widespread because it makes the employees feel like they have some power to strike back. Although not every company has a literal shredder hog, the term has been extended to apply to any deliberate action taken by employees that artificially increases the number of rejects, cull, waste, or otherwise unacceptable product.
The technique is also popular because it is so hard to catch. It is nearly impossible to prove that the employees are deliberately feeding the hog, which would require constant supervision. The other employees working in the area are likely to share the same gripes as the one feeding the hog and won't turn him in for it. Meanwhile the supervisor or manager responsible for maintaining quality or production control is collecting poor marks on his record with the company, and may get fired. If this happens, the employees may feel like they have "won".
Alternately, the supervisor could suspect that his employees are feeding the hog. Since this is usually caused by conflicts with the supervisor to begin with, the supervisor may retaliate by making conditions even worse for the employees. Breaks could become fewer or shorter, benefits could be reduced, verbal abuse could increase, raises or promotions could become harder to come by... the supervisor has ways to strike back at his employees as well. This cycle could well continue until the workers unionize or the supervisor gets fired. In either case, the company as a whole is likely to suffer in both the short and long term.
The ideal solution is, of course, to open channels of communication with the employees and try to reach some resolution or compromise on their problems. This can be extremely difficult if the employees have become hostile to the company and do not feel as though their concerns will be taken seriously. At the same time, the implication is that the company is trying to get them to admit what they are doing, which they would be understandably reluctant to do. Meanwhile the supervisor, if he is at fault, may be unwilling to admit that he is doing anything wrong — his harsh motivational tactics may seem justified to him or he may not want to admit to upper management what he did to instigate the breakdown in labor relations to begin with. In all, it becomes a very delicate situation with no easy or clear solution.
Many companies have turned to labor relations consultants to help them establish and maintain the kind of employee relationships that prevent this situation from occurring in the first place. If the employees can feel safe and respected when bringing their complaints to management, and if their suggestions are dealt with in a fair and timely manner, a company has little reason to fear their employees will begin feeding the hog.