As I pointed out in the video, it's relatively easy to conduct an online survey. But of course there are also major drawbacks compared to personal or telephone interviews: 1) Sample: it is difficult to draw a representative sample 2) Response rate: the response rate can be very low, which impacts the representativeness of the results 3) Data quality: There are no interviewers, nobody to "watch over" and motivate the respondents. They may not take the survey seriously or skip questions they don't want to anwer.
