I'm a student working on my B.E(CS) and my question is the following: 


Is testing in the software field needed? 
If we create a software with great care, then why should we test?  
After testing can we be sure that we have achieved this goal (the product/software works as intended) because we have done the testing for it? Is it possible?


My question: Is testing of software needed?

Yes.  Because no matter how good you are, you can't think of everything.  


You will also be asked to make your software do things that you never intended for it to do.  
You will also never have requirements that are so clear that you will be able to think of every possibility to make sure the code doesn't break.
You will also work with other people's software and apis that will not always work as intended, but you will assume that it does, or should, leading to a defects in your "perfect" case.

