This can be difficult to determine. Many modern software applications are so complex,and run in such an interdependent environment, that complete testing can never be done. Common factors in deciding when to stop are:
What is Test Data Collection?
What if there is not enough time for thorough testing?
What is Use Case
What is Total Quality Management?
How can new Software QA processes be introduced in an existing organization?
What are 5 common problems in the software development process?
What is I18N/L10N stand for ?
What is Internationalization (I18N)
What is localization (L10N)
Why is it necessary to perform security testing?