This wide influence is in part to the high level of practicality of Maslow's theory. This theory accurately describes many realities of personal experiences. Many people find they can understand what Maslow says. They can recognize some features of their experience or behavior which is true and identifiable but which they have never put into words. Maslow is a humanistic psychologist.
Humanists focus upon potentials.
They believe that humans strive for an upper level of capabilities. Humans seek the frontiers of creativity, the highest reaches of consciousness and wisdom. Maslow has set up a hierarchic theory of needs. All of his basic needs are instinctoid, equivalent of instincts in animals. Humans start with a very weak disposition that are then fashioned fully as the person grows.