B. f. skinner was a behaviorist; as such he would argue that the most important things that shape development are:

B.F. skinner was a behaviorist; as such he would argue that the most important things that shape development are "Rewards and punishments".
Reward and punishment are two sides of a similar coin. They are the two types of extraneous inspiration, which can be fairly noxious in the way it seems to work at the time. In conditioning, punishment stops activity while reward energizes it. 

Americans often speak of their country as one of several large regions.  these regions are cultural units rather than governmental units --  formed by history and geography and shaped by the economics, literature and folkways that all the parts of a region share. what makes one region different from another? a region's multicultural heritage as well as distinct demographic characteristics like age and occupation make regions different and special. within several regions, language is used differently and there are strong dialects. there are also differences in outlook and attitude based on geography.