Dear Kamendra,
Hope you are doing great,
I don't believe there is such a thing as an underrated IIM.
All IIMs have excellent faculty, strong leadership and a board of governors to guide them, and students who are likely to be among the brightest in the company.
The only difference is that some IIMs were established much earlier and have as alumni some of the Indian industry's experts. As a result, it is natural for students to prefer these colleges. However, there was a time when these older IIMs would have been in the same position as the so-called newer or underrated IIMs are today. So, in 10–15 years, some of the alumnus from the newer IIMs may make it big and the scene may change. In the end, the colleges provided you with an education.
I hope this will help you,
Best of Luck :)
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