According to the BABOK® V3 Guide, the purpose of measuring solution performance is "to define performance measures and use the data collected to evaluate the effectiveness of a solution in relation to the value it brings."

When we refer to performance measures, we are referring to those measures that can help us determine the value that a newly implemented or existing solution is bringing to the organization. In some cases, a solution may have built-in performance measures to track how much value is being generated by the solution, but in many cases, the business analyst needs to work with stakeholders to define these measures. Measures often take the form of key performance indicators that are in line with the overall organizational goals, targets, or predefined tests for a software solution. 

Let's consider the following real-world example:

Consider the situation where a new call center software solution has been implemented. One measure to determine whether the solution is performing as expected could be to measure the time spent to resolve a customer inquiry. A decrease in the time spent supporting customers during a single support call will be a positive performance result for the new solution. Another performance measure could be the number of positive customer feedback ratings that are recorded after each successful call.

Let's now consider the core elements that a business analyst should include when performing this task.