When selecting an optional subject for the UPSC Mains, candidates should consider several attributes. Personal interest and familiarity with the subject matter are crucial, as they directly affect motivation and understanding. The scoring potential of the optional subject is also essential; research on past trends can provide insight into what subjects have yielded high marks. Assessing the overlap with the General Studies syllabus can lead to efficient preparation. Furthermore, availability of resources, coaching options, and peer support can also influence the decision. A careful analysis of these factors leads to informed choices that enhance chances of success.