Why did hunter-gatherers stop roaming and settle down in villages?

I think your question is about primitive societies who were hunters and gatherers and used to move from one place to another.

The Hunter-gatherer did not stop his habit of moving abruptly. It was a gradual process and involved several factors and the cause for stopping roaming differs from place to place according to the environment they lived.

One of the key factors for this change in the primitive societies is rearing. When the primitive man found some cattle and other animals which could be raised and used for his food and daily living purposes, he started to make shelters both for himself and for the animals in grass fields where plenty of food and water for the animals was available abundantly. Alongside, he started to cultivate some early food grains and harvested them time to time which provided him some additional food. Thus, he found it more convenient to lead sedentary life rather than roaming and hunting for the food in the woods.