Detrimental studying habits for success in the UPSC examination include cramming, which hampers long-term retention of information. Inconsistent study schedules and procrastination can lead to inadequate preparation. Additionally, relying solely on rote learning without understanding concepts diminishes analytical skills. Moreover, neglecting current affairs and practical applications of knowledge can result in an incomplete grasp of the syllabus. Effective study habits should focus on comprehension, regular revision, and active engagement with material.