JEE Main percentile is used to compare your performance with other students. The higher your percentile, the better your chances of getting admission in good engineering colleges for B.Tech. Admission depends on your percentile, category, and available seats. Usually, colleges set cutoff percentiles for different branches. If your percentile is above the cutoff, you get a seat. Counselling happens based on your percentile and rank. So, scoring a good percentile is very important for B.Tech admission through JEE Main.