Measuring the relationship between potential risk and expected return when investing. A high ratio (e.g., 1:3) indicates attractive returns compared to the accepted risk. In Vietnam, investors apply this ratio to assess opportunities in volatile fields such as securities, real estate, or technology startups. The renewable energy or logistics sectors can provide balanced ratios thanks to supportive policies and increasing demand. It is necessary to combine diversification, fundamental/technical analysis to optimize decisions, and avoid greed when pursuing "super-fast" profits.