The effect of population growth can be positive or negative depending on the circumstances. A large population has the potential to be great for economic development: after all, the more people you have, the more work is done, and the more work is done, the more value (or, in other words, money) is created. So, surely this can be nothing but good. There’s a reason that farmers often have a lot of kids – more kids means more workers.
But, unfortunately, it isn’t that simple. In a country with abundant resources and money – a rich country – perhaps more people is a good thing. But that isn’t always the case in countries with limited resources. Limited resources and a larger population puts pressures on the resources that do exist. More people means more mouths to feed, more health care and education services to provide, and so forth. So, population can be a mixed bag.