While primary data collection is a powerful method for acquiring information, it does pose several significant problems including:
Compared to secondary research, primary data may be very expensive since there is a great deal of marketer involvement and the expense in preparing and carrying out research can be high.
To be done correctly primary data collection requires the development and execution of a research plan. Going from the starting point of deciding to undertake a research project to the end point of having results is often much longer than the time it takes to acquire secondary data.
Not Always Feasible
Some research projects, while potentially offering information that could prove quite valuable, are not within the reach of a marketer. Many are just too large to be carried out by all but the largest companies, and some are not feasible at all. For instance, it would not be practical for McDonalds to attempt to interview every customer who visits their stores on a certain day since doing so would require hiring a huge number of researchers, an unrealistic expense. Fortunately, there are ways for McDonalds to use other methods (e.g., sampling) to meet their needs without the need to talk with all customers.