This migration model shows the process by which the flow of migration is happening between two countries. There are two names for each flow which is the mainstream flow and the counterstream flow. The mainstream flow is when people leave their place of origin whereas the counterstream flow is when they return to their place of origin after going to their place of destination.
Usually, there is always a reason why people want to leave their place of origin. There are negative and positive reasons why people would want to migrate. The pull reason is the negative reason by which people would migrate. For example, they might not be getting good pay for work in their own homeland or they could be living in poverty. And the positive reasons are when they are attracted to the things in other countries which make them want to migrate to that new place.