KPI is an index, not an objective index, but it can be used to determine goals or standards of behavior. It is a tool for measuring the overall results of business performance and managing strategic objectives. The essence of assessment is to guide employees'attention direction and release their energy from trivial matters, so as to pay more attention to the company's overall performance indicators, department's important work areas and personal key tasks. It is mainly used to find key problems in management and quickly find the crux of the problem. Third, extract key indicators. Indicators should cover the main work areas of the evaluation objects, reflect the quality of the evaluation objects, and be controlled by the evaluation objects.