Taken again from Quora
All I can say is that the best mentor for IIT JEE preparation is "YOU YOURSELF".
No teacher is going to help you. Teachers will only show you path. You will have to travel the path yourself.
The famous quote goes as follows - "God helps those who help themselves"
Another good (or rather better) mentor for JEE preparation are "YOUR PARENTS". No matter what their profession is or what their educational qualification is, parents are always the best mentors.
My parents always helped me during my JEE preparation. The most important thing that you need to get into IIT is "motivation" and your parents will always motivate you. They will be always by your side when you need light on the path or when you are feeling low/depressed. They will selflessly help you.
The third best mentor is "BOOKS". Books will always help you. No matter what the problem is, it's solution can always be found in some or the other book. Books are not selfish. They will always be ready to give you knowledge and will never ask you for anything in return.
I hope you got your answer.
JEE preparation is not about having good Physics, Chemistry and Maths teachers.
Their are lakhs of students who don't have access to any kind of tuition/coaching. They are studying on their own. And many of them even crack JEE (with good ranks)
Once you get into IIT, you will realize that the teaching system is completely different. You will have to guide yourself. People hardly understand anything in the lectures/tutorials and professors will be least bothered about this. So, ultimately you will have to resort to books and of course yourself.