Problem: Why do interviewers cheat or falsify the survey responses? While the obvious answer is to "avoid doing work", prior research has suggested a number of factors that lead to interviewer cheating. They include deadline pressures, performance pressures, personal/family issues, time conflicts with other job(s), and cumbersome workload.
Interviewer falsification can be prevented or reduced by providing a supportive environment for interviewers. Other measures include appropriate design of studies, maintenance of "conspicuous deterrents". It is also important for a supervisor to engage in detecting any instances of falsification. Moreover, it is important to respond firmly and in a timely manner in case of interviewer misconduct.
You might want to focus on the following:
To what extent interviewer cheating is a problem in survey research? How is it different in the context of surveys conducted on the Internet compared to face-face or telephone surveys?