Need versus nice-to-have
After asking questions, you should have all user requirements. However, you'll need to answer a few more questions before continuing with the design:
Is everything that they've mentioned relevant?
Do they need to have everything in the new system?
What are the implications of this feature?
Should all requirements from every user be implemented in the system?
Do you have all the information that you need?
Does a better way exist for accomplishing this task with Dynamics 365?
After gathering the requirements, you'll need to separate the need-to-have from the nice-to-have requirements.
Nice-to-have - These requirements are what a user wants in the system but aren't needed for the system to work. Examples of nice-to-have requirements might be a certain aesthetic appearance of an app or that it saves time for only one person once a year.
Need-to-have - These requirements are the minimum that's needed for the system to work and how you should design your system. An example of a need would be a requirement to help users follow the laws and regulations of their country/region or industry. Another example of a need-to-have requirement is one that would save 20 hours for each user every week.