Well, these are two different things. IIT provides you with a B.tech degree and on the other hand, IAS is a public service.
There is a very clear one:
Have you ever seen an IAS employee trying to get an MBA from IIM or any other top university after becoming an IAS?
I have seen many IITians and IIMians studying for the civil service exam, even after they got very high placements on their campus and worked at that particular MNC.
By enrolling in IIT, you will always be able to earn well and maintain your IIT engineer tag. But to become an IAS employee, you have to study for the exam, risk your career. And even if you recover, professional life will be very difficult.
