Defects can be of various severity, and we need a classification (severity scale) to be able to assess and prioritize them, based on business impact.
We have 5 defect severities. Each defect is classified according to this severity scale . This classification is initiatede by reporter - and it can be changed during defect management, as defect analysis will make us wiser.
Defect severity classification is a useful tool in defining testing acceptance criteria. E.g. "no blocking or critical defects must be unresolved".
Severity | Description | |
|---|---|---|
| 5 | Blocking | A blocking defect which prevents further testing, and testing will be suspended |
| 4 | Critical | A critical defect, which disables the whole system and prevents useful operation for any significant length of time - complete loss of service. Business critical functions cannot be carried out, and it is not possible to recover. Critical to application availability, results, functionality, performance, security or usability. |
| 3 | Major | A defect, which disables a critical function within the system, causing severe loss of service. A defect that cannot be remedied by a work around, and the user is unable to proceed with selected function. |
| 2 | Normal | A defect which disables a function within the system and causes minor loss of service, but which the business can work around in the short term. A defect with medium business impact, but which impacts many users. |
| 1 | Minor | A defect which has minor functional impact and there is a simple work around. Or a cosmetic defect or incorrect positioning on a screen/report which causes no loss of service. |