What is a drawback of using diaries for data collection in market research?

Using diaries for data collection in market research can present several challenges, and one of the significant drawbacks is that they tend to be costly and often have high dropout rates. When participants are required to maintain a diary, it can involve significant time and effort on their part to consistently and accurately record their thoughts, behaviors, or experiences. This level of commitment can lead to fatigue or a sense of overwhelm, which may make participants less likely to continue with the study over time, resulting in high dropout rates.

Additionally, the cost associated with incentivizing participants for their time and effort, as well as the resources required for managing and analyzing diary data, can also add up, making this method less financially viable for some research projects. In contrast, instant feedback, ease of analysis, and minimal effort required from participants are generally not characteristics associated with diary methods, which helps underline why the correct answer focuses on cost and participant retention challenges.