Common mistakes candidates make while preparing for the UPSC exam include poor time management, lack of consistency, and neglecting current affairs. Many aspirants focus too heavily on one subject, resulting in an imbalanced preparation strategy. Relying solely on coaching materials without incorporating self-study limits the depth of understanding. Additionally, failing to regularly assess progress through mock tests can lead to unforeseen gaps in knowledge. Overlooking the importance of essay writing and interview preparation often hinders overall performance. Recognizing these pitfalls can help candidates develop a more effective and comprehensive preparation plan.