How to define effective metrics? What is the use of quality metrics?

The goal of software engineering is to develop a product that is of high quality. Metrics that are derived from these measures indicates the effectiveness of individual. Metric is a standard for measurement. A metric is a measure that captures performance and allows comparisons and supports business strategy.

The use of quality metrics is to spot the performance trends, comparing alternatives and predicting the performance. However, the costs and benefits of a particular quality metric should be considered as collecting data will not necessarily result in higher performance levels.

Effective metrics should define performance in quantifiable entity and a capable system exists to measure the entity. Effective metrics allow for actionable responses if the performance is unacceptable.

Identifying effective metrics is a bit difficult. Ranges can be identified for an acceptable performance of a metric. It can be referred as breakpoints in case metrics are defined for services and targets, tolerances, or specifications for manufacturing.

Breakpoints are levels where there is a chance that the improved performance will change the behavior of the customer. A target is a desired value of a characteristic. A tolerance is an allowable deviation from target value.