The UPSC allocates ranks to candidates based on their overall performance across all three stages of the examination—Preliminary, Mains, and Personality Test. Each stage carries a specific weight in determining the final ranks, which reflect candidates' aggregate scores. The final ranks influence the allocation of services and posts among successful candidates, as higher ranks provide better opportunities within the civil services. This system ensures that selection is merit-based and aligns with the candidates' performance, helping to maintain a level of integrity and transparency within the recruitment process.