Carl Rogers (1959) believed that humans have one basic motive, that is the tendency to self-actualize - i.e. to fulfill one's potential and achieve the highest level of 'human-beingness' we can.  Like a flower that will grow to its full potential if the conditions are right, but which is constrained by its environment, so people will flourish and reach their potential if their environment is good enough.

However, unlike a flower, the potential of the individual human is unique, and we are meant to develop in different ways according to our personality.  Rogers believed that people are inherently good and creative.  They become destructive only when a poor self-concept or external constraints override the valuing process.  Carl Rogers believed that for a person to achieve self-actualization they must be in a state of congruence.