Question

why some areas are more developed than other

Answer 1

Because any development activity depends
on the available of resources i.e, rich in minerals,water,etc .
Education also plays a vital role in this

Answer 2

Some areas are more developed when compare to other areas because only some areas have high soil fertility, resources, favourable climate, water etc.
These areas therefore have developed more faster then others.
And all the resources are never available in only one region.
But due to nature, the amount of resources in one area are in higher concentration when compared to that of other area.

Hope my answer helps you : )