How do you determine the right Key Performance Indicators $($KPIs$)$ to track for a particular warehouse? Provide examples and proof?

How do you find out if the metrics utilized reflect accurate information, like for example, the true cost of inventory management? Present evidence and supporting information?

How do you verify if people are doing their jobs, and how do you know they are working efficiently? Demonstrate facts and figures offering verification?

How can it be determined that the information actually captured for calculating metrics is relevant and current? Reveal methods, facts, and figures that support your answers?