How do you handle changing requirements during product testing?

Often requirements are modified as software/product development starts and stakeholders find gaps in requirements or design. As testers, it is important to understand the impacted areas and the reason for change. For example - if the changes are around a non-functional requirement, then it may not be worthwhile to do a thorough functional regression testing for validating the feature, while the focus should be on the new nfr requirement and design KPIs and tests to meet those KPIs. Test plan should clearly describe the scope of the change and how the change should impact the system

As a QA engineer, you should be able to think like the end user. You should test the product from multiple perspectives including that of the experienced end user, malicious end user, inexperienced end user and a new user. It is important to understand the reason for the changes to the product requirements and the impact on the product and its users. Usually, any changes to the original product requirements would mean running additional regression tests on the product to ensure that there's no breaking changes. However, One way to manage changing requirements, in my opinon would be product versioning. Making and releasing incremental changes to the product to test the effect on the product's infrastructure, users and business.

Communication is a key in product testing, as testers are the ones responsible for the verification of the product and therefore need to be aligned with business and product priorities. Product testers are the ones who are actually the first users of the product and also working with the developers and product managers in the same team. They are the ones who has a decent understanding of the development thought process, the requirements, and also they understand the customer user behavior to a good degree. So, they should be clear and transparent about the testing strategy, work with all stakeholders to identify business critical scenarios, train others about customer behavior, identify defects and builds trust between organizations.

It is always recommended to sketch real-world scenarios that effectively articulate customer behavior. One way of doing it could be using customer database dumps, identify usability patterns from there like Amazon prime day vs non-prime day customer behavior or giving thousands of query types to chatgpt to see how it responds. Every product is unique, and it is important to understand why customers prefer this product over others for a particular usage. Only by analyzing customer data dumps, it is possible to articulate their behavior and seek improvement in product.

MVP is an important thing when it comes to relationship building with customer and earning their trust. A MVP is usually representation of the core value proposition of the product. Testing should work hand in hand with product management in scoping the complexity of the MVP, it includes scoping system readiness, customer readiness definition, feature prioritization.

Product testing is an iterative thing and should continuously evolve with the product lifecycle. As more and more features are released, and our customers find more defects, it is important to understand the root cause of those defects and classify those defects like if they are a development issue or a new customer behavior or some other stuff. This helps in refining the test procedure, helping identify new scopes for product enhancements.

Accept the change and test - prioritizing risk based testing. But here's the secret, if you do this all the time anyway (risk based prioritization of testing) then the change doesn't have to impact your process. Learned from the greatest tester to ever support a product. You know who you are.