Final answer:
Portfolio management aims to improve investment returns through security selection or market timing, but it doesn't ensure economic success. Diversification helps reduce risk yet doesn't eliminate it.
Step-by-step explanation:
Portfolio management is the attempt to improve performance either by identifying misplaced securities or by timing the performance of broad asset classes. While effective portfolio management can enhance the potential for better returns, it does not guarantee economic success. A diversified savings and investing portfolio can mitigate certain risks and can be an effective strategy for long-term growth, but it is not a definitive assurance of economic success. Various factors, including market conditions, economic trends, and individual investment choices impact performance. Additionally, even with diversification, there can still be systemic risks affecting all sectors of the market.