Decolonization
India
Indias movement towards independence grew and got stronger in the early 1900s. Unfortunately this did not make a difference and Britian forced India to fight in WW2. India tried to have nonviolent protest but they ended up turning into violent protests which made the British want to leave. As religious tensions grew Britain decided to split India into two separate parts. India finally won their independence in 1947. They had many challenges after this, but their new prime minister stressed the need for unity and economic.
North Korea
North Korea followed the Soviets type of government by making themselves communist. The government controlled everything which resulted in problems. The foreign aid decreased and poverty and food shortages spread across the country. North Korea still continues to this day to be communist and suck at everything and deserve a bomb.
Question
The common cause to countries wanting independence is multiple different things. Countries want independence because other countries have control and are abusing their power. For example, India was controlled by Britain and did not like that and was forced to fight in WW2. Countries also would want independence to make their own laws and control their own destiny.