You can create a list of RMA reasons in SellerCloud. When creating an RMA later, you can select the reason from this list. This functionality allows you to create a specific workflow and define the reasons, making them easy to access for all your employees.
Normally a list of the most used reasons for returns is available by default in SellerCloud. Those reasons are marked as global.
To create your own RMA reasons navigate to Settings> RMA Reasons. Type the reason on the top and add it to the list.