When to Start and Stop Software Testing ?

• When software testing should start?

A most frequent and important question asks in interview as well as arise in the SDLC phase that "When should start a software testing?"

So, Testing starts as early as initial phase i.e. Requirement gathering phase and continues till Release/Maintenance phase. The purpose of testing as early in the requirement phase, because if we found any defect or issue in the later phase of SDLC, then the cost of fixing bugs is raised. Therefore, to overcome from this situation, we must need to start testing at the right from the initial phase of SDLC.

• When to stop Testing?

Another most important question from interview perspective is:- "When to stop testing?"
Here are few things we should keep in our mind before stop Testing of any application or product:-
1. Bug rate reaches below down a certain level.
2. Tester should stop testing when testers are not getting high priority bugs.
3. Stop when tester meets the project deadline.  
4. Less ratio of critical bugs.
5. Test budget has reaches its limit. Or comes to an end.
6. Stop when Alpha testing and Beta testing gets completed.
7. Stop when code/design, functionality and requirement reaches a specific point.