I think it's incorrect to label it an "exam" scam. It's really a scam about recruitment to government jobs. India has this weird system where almost every good government job has an exam that you're supposed to take to get that job. These exams are held once a year or so and all that matters is your performance in that exam and maybe an interview. This makes it impossible for anyone from private industry to take such a job. So what you get instead is a bunch of lifers who continue the cycle of corruption.