@Shailputri upsc at every level levels the game . Experience ones won't put that much of effort as they got bored of reading same thing again and again , but they have accommodative themselves with exam , and they know what to do , how much to do . Freshers prepare with zeal and much intrest but lack that accomodation with exam . At the end it all depends how you calm your nerves after a avg preparation , either in prelims , mains or interview .
