Defect Severity in Software Testing

               In software testing, defect severity can be defined as the degree of impact a defect has on the development or operation of a component application being tested.

Higher effect on the system functionality will lead to the assignment of higher severity to the bug. Quality Assurance engineer usually determines the severity level of defect  

Defect severity can be categorized into four class

• Critical: This defect indicates complete shut-down of the process, nothing can proceed further
• Major: It is highly severe defect and collapse the system. However, certain parts of the system remains functional
• Medium: It cause some undesirable behavior, but the system is still functional
• Low: It won't cause any major break-down of the system.

Tips for determining Severity of a Defect

• Decide the frequeny of occurence: In some cases, if the occurrence of a minor-defect is frequent in the code, it can be more severe. So from user's perspective, it is more serious even though it is a minor defect.
• Isolate the defect: Isolating the defect can help to find out its severity of impact.

• A very low severity with a high priority: A logo error for any shipment website, can be of low severity as it not going to affect the functionality of the website but can be of high priority as you don't want any further shipment to proceed with wrong logo.
• A very high severity with a low priority: Likewise, for flight operating website, defect in reservation functionality may be of high severity but can be a low priority as it can be scheduled to release in a next cycle.