Seven Principles of Software testing

Software Testing focuses on ensuring the quality of the software. Software not tested properly can cause many problems including financial losses, reputation loss and at times injury or even death. How much testing is required depends on the risks associated with the software as well as time constraints. There are few principles of testing that can help to better understand the process of testing and define testing process

The principles of testing are as follows:

1.  Testing shows presence of defect  

Testing helps in uncovering defects although we can never be sure that that there are no defects in the software even after testing. So the focus of testing is to find as many defects in the system.

2.  Exhaustive Testing is not feasible

 Going by the first principle, tester can never be sure that there are no defects in the system, One of the reason for first principle is exhaustive testing is impossible. We can test all the scenarios related to software but the time and resource cost for testing exhaustively will be so huge, it will not bring any value and will not be able to deliver software. Due to this proper risk analysis and priorities of scenarios should be taken care of in testing for balanced and timely testing completion.  Test cases should be prepared based on the functional specification, as test cases for high priority scenario should be executed first.

3.  Testing should start as early as possible

 Catching defects early in the Software development life cycle reduces the cost of fixing of defect. For e.g. Testing should start as early as possible, Reviews should take place to identify gaps in requirements understanding, and identify code issues early.  Also test designing should start as soon as possible.

4.  Most of the Defects are confined to small module

This has been noticed that most of the defects are confined to small module; the reason of defects can be understanding gaps in the particular set of modules and the technical skill of the resources.

5.  Pesticide Paradox

 Executing the same test cases again and again eventually results in no defects being identified by test cases. Due to this reason test cases should be reviewed from time to time, with new test cases added and redundant test cases removed from the regression pack to keep the test suite fresh, up to date and effective. Test cases must include both manual and automated test cases for higher coverage of test scenarios.

6.  Testing requirement varies from software to software 

Testing is done differently for different software. A social networking site will have different requirement of content and performance testing compared to banking software that will require functionality and security as main factors compared to the social networking site. The testing requirements should be well defined in the scope of testing.

7.  The software developed should be usable by user

and should meet user’s need and expectation. It does not matter if there were no defects in testing the software if it does not meet the need of end users.Software