William Ouchi's Theory Z recognized Multiple Choice the combined benefits of Theory X and Theory Y style managers, particularly the motivation by fear of Theory X managers and the belief that employees like work, as perceived by Theory Y managers. the combined efforts of Frederick Taylor and Elton Mayo, and created a hybrid approach to management that reflected Taylor's concern for productivity and Mayo's lesser concern for the human side of management. the merits of a hybrid form of Japanese-style management and American style of management. that conformity was the only way to manage successfully..