Abraham Maslow's Theory of Motivation was intricately linked to his hierarchy of needs. Maslow believed that people were motivated by real or perceived needs in their lives, and that these motivators could be internal or external.
At the foundation of Maslow's theory are two sets of 'lower needs'. In short, people are driven by the most basic physiological needs: air, food, water and sleep. They are therefore highly motivated to obtain these things.
At the next level resides the need for safety; this includes shelter, financial security and even health care.
The next level is where things become more complex; social needs bring interaction with others into the mix. This is the first of the 'higher level' sets of needs. The need for acceptance, for friends and companionship, and to 'belong' kick in, motivating people to modify their behavior.
Directly related to the social needs level are needs relating to aesthetics and knowledge.
These cross the barrier between what one wish others to think of them, and what they think of themselves - they may wish to look beautiful or be knowledgeable equally for their own sake and for the impression they may make on others.
Self-esteem is the next level; the desire to be accepted by others gradually morphs into a need to view oneself as worthy.
This level has two sets of motivators: internal and external. The need for recognition, reputation, attention and social status are activated by external motivators, while actual accomplishment, self respect and self-esteem stem from internal motivators.
Self actualization is the mountaintop of contentment reached by meeting all needs and reaching a plateau of extreme happiness, according to Maslow's theory of motivation. Maslow felt that very few individuals ever reached this level, becoming bogged down instead in the next to last phase.
Self actualization is supposed to be an ongoing quest to realize one's full potential. The needs evolve as the person comes closer to fulfilling them, meaning that they are never quite achieved. Motivators for self actualized people often revolve around truth, justice, wisdom and 'meaning'.
Satisfying needs is not to be considered selfish. The manner in which needs are met, however, can be selfish; it is part of personal growth to reach a point at which unselfish acts are possible. If needs are met appropriately, the individual is actually filling in 'deficiencies' in his or her life, and becoming a more healthy, balanced person.