BSE MD & CEO says When Sensex was relaunched, Friday was chosen for expiry after market consensus
Expiry days are "sweet spots" but due to concentration risk, it shifted to Wednesday
With "one expiry, one exchange," NSE chose Thursday, so BSE took Tuesday
BSE MD & CEO says Global risk events happen daily, not just weekends
If a product expires midweek, traders need another contract to hedge risk
Without this, they pay for a full week instead of a few days, raising costs
This also leads to concentrated positions in a single product