Final answer:
Using only one metric often fails to capture all necessary information, making it an unwise practice. This is true for concepts like majority rule, unemployment rate, and BMI, all of which have limitations in fully describing their respective situations.
Step-by-step explanation:
True, it is unwise to only use one metric because it fails to tell the whole story. This is due to the fact that a single metric often does not account for all variables, contexts, or nuances relating to a situation. For example, the majority rule in decision-making can fail to produce a single preferred outcome when there are more than two choices, leading to a situation known as Condorcet's Paradox. Similarly, unemployment rate can be a misleading indicator of overall joblessness as it does not account for underemployment, discouraged workers, or those not actively seeking employment. Additionally, using BMI (Body Mass Index) as a sole indicator for weight and body fat can be misleading as it fails to distinguish between muscle and fat mass, nor does it account for distribution of body fat.