In Software Engineering, we chant the term of validation and verification a lot between the software team members. Actually, it is used across the software project phases and I think there is a misconception in understanding the two terminologies and when to use them.
Software Testing is vital for any software development life cycle, it is fundamental to ensure the software quality and to have a workable functional software at the end of the project.
“Testing is any activity aimed at evaluating an attribute or capability of a program or system and determining that it meets its required results” Bill Hetzel, 1988
The main motive for the testing is to ensure that all functionalities are working correctly as per the requirements. It is not only that this is the basic purpose of testing, while It is important to test how to break the system, how to simulate the abuse of the system by the quality team before someone else does that for you and it will be a disaster at this time.