As with any exploratory research design, focus group interviews are not a perfect research method. The major weaknesses of focus groups are inherently similar to all qualitative methods: the findings lack generalizability to the target population, the reliability of the data is limited, and the trustworthiness of the interpretation is based on the care and insightfulness of researchers. Focus groups have an additional drawback: the possibility that group dynamics contaminate results.
While the interaction between participants can be a strength of focus group research, groupthink is possible as well. Groupthink happens when one or two members of the focus group state an opinion and other members join the bandwagon. Groupthink is most likely when participants do not have a previously wellformed opinion on issues discussed in the group