Hey

Though seats are get filled in the first cut off but there always remain few seats vacant in many colleges as well. Sometimes, admission gets closed in the second cut off for a specific course. But in the next cut off, admission are again restored and cut offs are slightly decreased, therefore candidates gets chance to take admission in a college.

This usually happen because in the first cut off, candidates secure a seat in a college and as further cut offs are released they switch between colleges and course so seats become again vacant.

I hope you understood. Thanks