Its a good question. Most of students follow coaching institutions for any kind of exam. but it is not necessary to clear any exam.
If you can do self studies then it is not important to get coaching for CLAT and AILET, but coaching institutions guide you to how to manage time for solving paper in less time or how to solve some tricky questions or what sequence to follow. These things give benifits in exams.
So its depends on you if you can manage on your own then its not important to get 1 year coaching.
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