What's your strategy for prioritizing system defects and test cases?

1 Defect severity and impact

One of the most common ways to prioritize defects is to classify them according to their severity and impact on the system and the users. Severity refers to how much the defect deviates from the expected behavior or output, while impact refers to how much the defect affects the functionality or usability of the system or the user experience. For example, a defect that causes the system to crash or lose data is more severe and impactful than a defect that causes a minor cosmetic or layout issue. You can use a scale of low, medium, high, or critical to rank the defects based on their severity and impact, and assign them to different levels of urgency and resources.

2 Defect frequency and risk

Another way to prioritize defects is to consider how often they occur and how likely they are to cause serious consequences or damage. Frequency refers to how often the defect is encountered or reproduced in the system, while risk refers to how much the defect exposes the system or the users to potential threats or losses. For example, a defect that happens rarely or randomly is less frequent than a defect that happens consistently or predictably. A defect that exposes the system or the users to security breaches or legal liabilities is more risky than a defect that does not have such implications. You can use a matrix of frequency and risk to categorize the defects into different quadrants, and prioritize them accordingly.

3 Test case importance and relevance

Similarly, you can prioritize test cases based on their importance and relevance to the system and the requirements. Importance refers to how much the test case covers the core functionality or the critical scenarios of the system, while relevance refers to how much the test case aligns with the current objectives or the changing needs of the system. For example, a test case that verifies the main features or the most common use cases of the system is more important than a test case that checks the secondary or the rare aspects of the system. A test case that reflects the latest requirements or the feedback from the stakeholders is more relevant than a test case that is outdated or obsolete. You can use a score or a weight to measure the importance and relevance of each test case, and rank them accordingly.

4 Test case dependency and coverage

Another factor that can influence the prioritization of test cases is the dependency and coverage of each test case. Dependency refers to how much the test case depends on the output or the outcome of another test case, while coverage refers to how much the test case covers the different inputs, outputs, or paths of the system. For example, a test case that requires the execution or the completion of another test case is more dependent than a test case that can be run independently or in parallel. A test case that covers multiple or diverse scenarios or conditions of the system is more comprehensive than a test case that covers only one or a few cases. You can use a graph or a map to identify the dependency and coverage of each test case, and schedule them accordingly.

5 Test case automation and maintenance

The last factor that can affect the prioritization of test cases is the automation and maintenance of each test case. Automation refers to how much the test case can be automated or executed by a tool or a script, while maintenance refers to how much the test case needs to be updated or modified due to changes in the system or the requirements. For example, a test case that can be automated or executed by a tool or a script is more efficient and reliable than a test case that requires manual intervention or verification. A test case that needs to be updated or modified frequently or extensively due to changes in the system or the requirements is more costly and time-consuming than a test case that is stable or consistent. You can use a matrix of automation and maintenance to evaluate the cost and benefit of each test case, and optimize them accordingly.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?