Primary data is data that you yourself have collected first hand for your research examples include conducting a survey and/or interviewing managers. Secondary data is data that someone else collected e.g. facts and figures from the annual report and articles in the business and financial press.
Primary data takes time to collect and designing a survey and conducting reliable and focused interviews are also specialist skills which most students do not yet possess unless they have had an opportunity to study a Research Methods course. If you have not studied Research Methods, it is unlikely that you will be strong at conducting reliable surveys, and if the survey questionnaire is poor then the subsequent analysis is likely to be poor. Not surprisingly, this leads to higher failure rates for topics that are mostly based on primary data.
The pass rate for topics using secondary data has always been higher – mainly because there is usually more secondary data available (IF you choose your company carefully) and so there is scope for developing a deeper and more substantiated analysis and evaluation.