Avoid and rectify errors.
Ensure that key functional and non-functional requirements are examined.
Testing is not about removing defects, but about notifying developers about them.
Testing is also about reducing risk in releasing.
Testing can give confidence in the quality of the software if it finds few or no defects.
Tests can and must be measured.
Typical measurements are:
- Number of defects found
- Number of failures in a given time period (reliability)
- Usability rating