Hi Hiresh ,
There are various reasons for not making into IIT's , To start with its your Rank and performance in JEE. One might have studied hard but if the efforts are not in the right direction you may not be able to get through .
Thus it can happenen even when you people have worked hard still you might not be able to crack JEe.
feel free to post as many as doubts you have we wud be happy to help.
All the best !!!
Anshul