Why do Polygraph?
It starts with one bad apple!
Integrity is not simply a personal virtue but a social one as well. In fact, there may be no other virtue in which an individual's personal cultivation of it has such a large effect on society as a whole. When one individual decides to act in a dishonest manner, his example can influence someone else to do likewise, resulting in a domino effect that lowers the standards and values of an ever-widening group of people.
Dishonesty has a slow creeping, socially erosive effect. As the virus spreads from one person to another, a new, less ethical code of conduct develops. And although it is subtle and gradual, the final outcome can be disastrous. This is the actual cost of even minor instances of stealing or fraud and the reason we need to be more vigilant in our efforts to curb it.
Dishonesty is no abstract idea. It surely starts with a few individuals who are willing to let things slide. Those around them see that this is the sub-standard norm and begin to adopt the same sub-standards. When new employees are introduced into the work environment, they adapt to the existing sub-standard culture of the existing bad apples in your organization. Even contractors, suppliers, and other stakeholders can end up infected by the same disease they were supposed to cure.