We use averages because they are useful for comparison. Just as we use different criteria to compare students based on height, health, or talents, we need a single criterion to compare the development of different countries. Averages allow us to summarize complex data into a single figure, making it easier to rank or compare different entities.

However, there are significant limitations to using averages. The primary limitation is that averages hide disparities. An average figure does not show how the total is distributed among the people. It may present a rosy picture while hiding the fact that the benefits may only be going to a select few.

We can illustrate this with an example related to development using two countries. Consider Country A, where citizens have incomes of Rs 9500, Rs 10500, Rs 9800, Rs 10000, and Rs 10200. The average income is Rs 10000, and most citizens earn close to this amount. In contrast, consider Country B, where four citizens earn only Rs 500 each, but one citizen earns Rs 48000. Although Country B might have a higher average income than Country A, the average hides the massive disparity in income. In Country B, most people are poor, whereas in Country A, there is equality. Thus, averages do not reveal the true picture of development or the distribution of income within a country.