1. Their answers have a lot to do with their positions. Objectively speaking, their views are somewhat biased. But relatively speaking, I agree with Zhang Hai. Wang Li mainly explains from the positive correlation between production quality and sales quality, so he thinks the whole process is a system, so he tends to be systematic; Chen Yu agrees with contingency theory by denying the meaning of system; Zhang Hai looks at these theories from the perspective of sales, and thinks that customers' needs are not fixed, but varied, so sales should be promoted according to their different needs. Li ke thinks that theory has no guiding effect on time, which is unscientific in itself. Generally speaking, the reasons for this inconsistency may include the personality characteristics, knowledge literacy, position type, temperament type and so on.

He thinks that only money is the best reward and the only way. This view ignores the diversity of people's objective needs, spiritual needs, psychological needs and self-realization needs, which is too one-sided. His view belongs to the typical X theory.

3. Theory does not help management, and theory does not help guide practice. This view is conceited and unscientific at the same time. In actual management activities, scientific analysis of specific situations and adverse environment and comprehensive application of relevant theories to guide practice can reduce detours. But in fact, the knowledge in books is not necessarily correct, so in practice, we should not only learn to use knowledge well, but also test and correct it.

Thank you, I hope I can bring you some help.