Of the different software development lifecycles, V model comes very useful in managing complex projects. Known as the verification and validation model, the peculiarity of this model is that development and testing happen side by side. That means whatever the developing team has developed is checked by the testing services team so as to reduce the possibility of errors. This model helps the QA test management team in ensuring the quality of the product better than other models. 

But for every process there are some drawbacks. The two important drawbacks of V model are that it’s time consuming as well as expensive. So if the requirements are perfect and clear it is always better to go for the less expensive models.