A candidate's rank plays a crucial role in their selection for services in the UPSC examination. The rank determines eligibility for various services, including Indian Administrative Service (IAS), Indian Police Service (IPS), and other central and state services. Higher ranks correlate with preferred postings and services due to limited vacancies. The final selection is influenced by both marks obtained in the examination and the category under which they fall. Consequently, candidates aim for top ranks to secure their desired services, making rank a significant aspect of the selection process.