The different methods have different goals and produce very different results. Designers complain that the methods used by marketing don’t get at real behavior: what people say they do and want does not correspond with their actual behavior or desires. People in marketing complain that although design research methods yield deep insights, the small number of people observed is a concern. Designers counter with the observation that traditional marketing methods provide shallow insight into a large number of people. The debate is not useful. All groups are necessary.
