Common pitfalls candidates face while preparing for UPSC include poor time management, inadequate understanding of the syllabus, and reliance on a single resource. Many aspirants overlook the importance of current affairs and fail to integrate it with static subjects. Neglecting revision and practicing mock tests can lead to a lack of confidence. Emotional factors like anxiety and burnout also play a significant role, causing candidates to lose focus. Setting unrealistic goals and timelines can lead to disillusionment. Proper planning, consistent study, and seeking guidance can mitigate these pitfalls.