When a pot is built up from the base by hand, it is impossible that it should be perfectly round. The solution to this problem ia the potter’s wheel, which has been a crucial factor in the history of ceramics.
It is not known when or where the potter’s wheel is introduced. Indeed it is likely that it develops very gradually, from a platform on which the potter turns the pot before shaping another side (thus avoiding having to walk around it). By about 3000 BC a simple revolving wheel is a part of the potter’s equipment in Mesopotamia, the cradle of so many innovations.