STI stocks are dropping every day. Would it be rational to sell away own shares to cut losses?

If you were a trader, you'll have to exercise tremendous discipline to cut your losses in this current market. (Or you might short or do CFD, but that's another topic totally).

However, as an investor, if the businesses we are owning a piece of continue to be good and resilient and we believe that they should emerge from this situation eventually, and we did not leverage to buy these shares, then why would prices going down make us worried?

Go back to your investment objective. Reflect upon why you bought these shares in the first place.

Conduct fundamental analysis to determine whether these stocks will be able to help you achieve your investment objectives.

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