Since in reality, the application will work in a certain way, it is much cheaper to first figure out and work out at the analytics stage exactly how this or that functionality will work.
At this stage, we determine preliminary project assessment and scope of tasks; preliminary project budget. So that we, together with the customer, have the same understanding of the result, purpose, and functions of the product, a business analyst is included in the project.
The purpose of this stage is to define the detailed requirements for the system. In addition, we need to make sure that all participants have correctly understood the tasks and how exactly each requirement will be implemented in practice.
Sometimes, testing specialists also participate in the discussion, who, already at the stage of requirements development, can introduce their own wishes and, if necessary, adjust the process.