Although the example that I will provide is more related to electrical engineering, I hope it helps you understand verification and validation in a better way. The company I used to work for was in charge of a project involving a transformer installation. The client was interviewed by the engineer in charge of the project on what he wanted specifically and how he wanted it. Days later, the team went to install the transformer as planned. When we were done the transformer was working perfectly but the client decided at the last minute that he did not like the location of it. Although it was a lot of more work, we were forced to change its location. This product was validated because it fulfill the client’s needs, it provided enough voltage for the client’s house and the current was flowing as expected. However, this product was not verified because the client was not happy with it so the project team had to do something about it.