Common mistakes candidates make while preparing for the UPSC include inadequate time management, neglecting current affairs, and relying excessively on standard books without practical application. Many aspirants also fail to develop a clear study plan, leading to inconsistent preparation. Others overlook the importance of mains answer writing and mock interviews, which can limit their performance. Candidates often underestimate the significance of revising and integrating core concepts across various subjects. Additionally, failing to analyze past papers may lead to misaligned efforts in preparation.