1.they does not have basic knowledge in their research topic.
2.they doesn't have correct procedure to do experiments.
3. The problem statement is not defined or very poor problem statement ( not a well defined statements).
If the problem statements is not defined properly by the supervisor, the researchers does not have the direction. Then, they cannot move anywhere. They always do something regarding research, but they do not know why they are doing it. So, improper problem statement is a major factor that makes research to be failed.
Above are the main reason for lack of interest)
What are things needed to increase research interest of a student.
1.Teach the fundamentals of their research topic. Make them to do basic experiment or simulation in their topic.
2. Define problem statements properly.
Once, they are very clear of basic theory, basic experimental procedure and problem statements, they starts doing research interestly.