Why is it that most chartered accountants go unplaced at IIM Ahmedabad?

One of my cousins was in IIM Ahmedabad and he had around 20–30 Chartered Accountants in his batch. And the General Secretary of the batch was a chartered accountant.

Other Chartered Accountants were either busy taking remedial classes for other students or were busy preparing for IB, consulting, or financial roles.

Moreover, All CAs got placed when only 30–40% of the batch was placed.

They do better than most of the engineers and others comparatively.

Actually, MBA is designed for commerce graduates itself. Engineers and others do have their share. However, according to trends, commerce graduates perform better. It is true that some engineers get better placements than CAs, but that's only because engineers make 80–90% of the batch.