图2阐述了从高层次到低层次需求是如何被追踪的。
Figure 2 illustrates how requirements are traced from the top level down.
那些负责任的编辑和记者们会在更高层次去引导和教育他们的受众，而并非一味迎合人们的低层次需求。
Responsible editors and reporters like to think they do not pander to people's basest interests, but rather guide and educate them.
此外，从高层次向低层次追踪需求，追到设计、编码、测试，你很容易看到需求变更的影响。
In addition, by tracing from high-level to low-level requirements and on to design, code, and test, you can easily see the impact of a requirements change.
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