Answer: Because people are both the producers and the consumers of all goods and services.
- A large population provides the manpower needed in agriculture, industry, transport and services.
- Human beings have skill, knowledge and technology, and are therefore called human capital; with education and training they produce more than machines alone can.
- A large population gives a big market for goods, which encourages industries and trade.
- People also pay taxes and provide the scientists, doctors, teachers and soldiers on whom the progress of a country depends.