People do what you pay them to do. So if you want to improve customer service, you need to pay people more for hitting service quality goals, right?
Almost right. There's always two ways to hit a target: improve your aim, or move the target. If cheating is easier than improving, then many people will choose to cheat.
The latest example of moving the target (here's an earlier example) comes from a former employee of a Toyota dealer whose job it was to make sure the dealer got the highest possible satisfaction scores on customer surveys.
His approach? Bribe customers to return their surveys directly to the dealer, so the dealer could complete the blanks ones and discard the negative ones.
Of course, this ensured that the dealer continued to get its performance bonus from Toyota. In the bigger picture, though, it probably had a negative effect on actual satisfaction. Customers aren't dumb, and most of them likely figured out what the dealer was up to.
This kind of game-playing has a corrosive effect on both the survey process and commitment to satisfaction. When some people openly cheat the system, it makes it harder for the honest people to demonstrate their comparative quality, and undermines the credibility of the survey. Employees then begin to question why the company persists in using such an obviously defective way to measure performance, and conclude that the company doesn't actually care about service, just survey scores. That makes them more willing to cheat, which undermines the survey even further.
The best solution is to use a survey process which is harder to manipulate. Sometimes, simple changes to a survey process can make cheating easy to detect.
In addition, if customers understand that the survey is taken very seriously (and that the dealer might cheat), they are likely to be more vigilant about protecting the survey process. It could be as easy as adding a cover letter which instructs customers: "To help preserve the accuracy of this survey do not turn it in to your dealer. Please place it in the enclosed envelope, sign your name across the sealed flap, and mail it from home." This will not only make it harder to cheat, but send the message to customers that the company takes the survey seriously--and as such may have the side-effect of improving response rates.
The key, though, is to be aware that not all employees are honest, and for the survey to work it has to be perceived as credible, fair, and not open to manipulation.