Mental stamina plays a crucial role in UPSC exam preparation, as the exam itself demands prolonged concentration and perseverance. Candidates must develop resilience to manage the extensive syllabus and the pressure associated with multiple examination stages. Building mental stamina can involve regular practice, disciplined study schedules, and incorporating balanced breaks. Techniques like meditation or mindfulness can enhance focus and reduce stress levels. Ultimately, maintaining a positive mental attitude contributes to better retention of information and effective performance under the challenging circumstances of both prelims and mains.