The most dangerous and common mistake that can be made in a market research is being biased. Most of us are bound by some preconceived notions about certain subjects and we react accordingly without completely clarifying or interpreting clearly. Such cases can lead to wrong research results even though the data might be correct. Hence, we need to stay free from conformation bias while doing market research.
To know more kindly visit:-
http://www.forbes.com/sites/rogerdooley/2013/08/21/market-research-mistake/