External Commercial Borrowings in Indian Context

I was trying to understand ECB recently and while browsing through the RBI official page I have found that ECBs cannot be used for

a) Real estate activities.

b) Investment in capital market.

c) Equity investment.

Reference Link

I am able to understand the help ECBs can bring to Indian entities by getting cheap credit when in need from High Income countries, but I am not able to understand what harm ECBs would do to the above three entities. What is the rationale ECBs are not allowed in these sectors?