Answer:
The presence, or absence, of states has come with the development of nations and the increase of settlement and growth of population. The reason for this is that as more people, with more differences between them, and also similarities, got together in pieces of land, they needed an intermediary who would take care of matters that, for large numbers of people, it was not possible to deal with individually.
Stateless societes existed particularly in prehistoric times, especially in hunter gatherer societies and in pastoral societies. In these cases, individuals and small groups of people formed together around a leader, but each one played a part in how things were run, and the decisions that were made. But these advantages worked for the small groups. The disadvantages were that these small groups were more vulnerable and prone to being destroyed, or dismembered, because of the lack of organization in their systems.
However, as population growth grew, and they settled down in specific land, tasks, needs, and activities also began to grow and develop and thus, as settlement grew, people saw themselves in need of having a state organized, a state that would see to the needs of the group, thus leaving the group to deal with other tasks that were also necessary for advancement, like food production and manufacturing. As these needs grew, leaders started to appear, and monarchies were among the first systems of government that arose in society.
The advantage of these monarchical societies, including hereditary societies, were, that they provided a sense of stability and protection, and people relegated to them activities that were once dealt with by the entire group. The disadvantage was that these monarchical systems turned towards control and power, ambition, to drive their societies in their own favor, and not in favor of the entire group.
These are only a few of the advantages and disadvantages both of stateless systems and monarchical and hereditary monarchies.