Principles of testing.

Principles of testing:

1. Testing shows the presence of defects, not their absence. Even if tests pass, it does not guarantee the absence of errors.

2. Complete testing is impossible. Due to the vast number of possible scenarios, it is impossible to verify everything.

3. Early testing. The earlier testing begins in the development lifecycle, the cheaper and more effective it is to fix errors.

4. Defect clustering. Most errors are concentrated in a small number of modules or components.

5. Pesticide paradox. Running the same tests repeatedly stops revealing new errors; tests need to be regularly updated.

6. Testing depends on the context. Testing approaches and methods depend on the type of application, requirements, and environment.

7. Lack of testing does not lead to quality. Quality is achieved not only through testing but also through proper development and processes.

These principles help in building effective testing strategies and managing risks.