It seems like you're asking about a specific coaching center in Delhi called Sigma Institute. To determine why it's considered the No. 1 coaching center, you'd typically look at several factors: 1. Success Rate: Does Sigma Institute consistently produce high achievers? Are their students securing top ranks in competitive exams? 2. Quality of Faculty: Are the instructors highly qualified and experienced in their respective fields? Do they have a reputation for delivering effective teaching methods? 3. Study Material and Curriculum: Does Sigma Institute provide comprehensive study materials and follow a well-structured curriculum that covers all exam syllabi thoroughly? 4. Infrastructure and Facilities: Are the classrooms equipped with modern amenities conducive to learning? Do they offer additional support such as libraries, labs, or online resources? 5. Feedback and Reviews: What do current and past students say about their experience at Sigma Institute? Positive testimonials and reviews can indicate the quality of education provided. 6. Track Record: How long has Sigma Institute been in operation, and what is its track record over the years? Consistent performance and continuous improvement are indicators of reliability. 7. Innovative Teaching Methods: Does Sigma Institute employ innovative teaching techniques to enhance learning and retention among students? 8. Focus on Individual Development: Does the institute personalize its approach to cater to the strengths and weaknesses of individual students? 9. Extra Support: Does Sigma Institute offer additional support outside of regular classes, such as doubt clearing sessions, mock tests, or counseling? 10. Value for Money: Considering the fees charged, do students and parents feel that the education provided at Sigma Institute offers value for money? If Sigma Institute excels in most or all of these areas, it's likely considered the No. 1 coaching center in Delhi. However, it's essential to verify these aspects through research, testimonials, and possibly visiting the institute before drawing a conclusion.