Final answer:
The difficulty in agreeing on a common definition of quality of life is due to various factors, including regional income differences, changing community values, and individual experiences.
Step-by-step explanation:
The difficulty in agreeing on a common definition of quality when it comes to quality of life is due to several reasons. First, average income varies in different regions of the country, which means that people in different areas have different standards of living. Second, community values influence definitions of quality, and they are subject to change over time. What may be considered important for quality of life in one community may not be the same in another. Third, individual experiences influence perceptions of quality in different ways, making consensus difficult. What one person may consider a high quality of life, another may not.