Explain the importance of developing metrics.

Metrics are numerical methods of measuring the performance or evolution of processes or phenomena.
Having an objective set of criteria to assess differences in a process from start to finish, to identify changes at the midpoint in a process, or to assess quality, is needed to help drive improvements. Metrics can offer insight into performance and highlight priorities that need attention.
Moreover, common, widely-accepted metrics can be used to reject, refine, or validate hypotheses which can, in turn, help develop theory. A weak theory is frequently reflected in the absence of common, widely accepted metrics.
One example of metrics used effectively in the social sciences is in citation measurement. Indices such as the H-score use common metrics such as the number of citations an article has received in scholarly journals to determine its significance and importance. This provides an objective manner of determining quality, versus subjective evaluations such as personal preference.