We are now aware about the term Bug/Defect.
Now the question arises – From where do they come from? From where do they arise..?
It is not fix that Bug will arise at this particular point or in this module of a software … we cant say or declare this. But we can predict the possibility or we can judge that this is the Bug prone module or area, depending upon the criticality or any other criteria. on the basis of this we can focus more on that area to test.
Generally Defect or Bug may arise at any stage or state. From the very beginning of project or at the closure stage or in between at any state.
Basically it arises from –
- At any stage of SDLC
- Error in any document Specification or Design or Test case or in the implementation of software/system
- Lack of Product knowledge and functionalities to tester or developer i.e. Error in use of system
- Environmental conditions i.e. wrong setup of testing environment
- Intentional damage
- Potential consequences of earlier errors
Its all about learning 