When you determine that a particular group isn't necessary anymore, you can proceed to delete it. In order to do this, first you need to go to the Scope section of the group you want to manage.
When you get to the Scope section, scroll all the way down until you see the part called Delete this group that has a button with the same name. Be aware that this section will only appear if you have the appropiate authorization.
After clicking on this button a window will appear in which you will need to type the name of the group you are currently managing. Before this, make sure that you want to proceed with the deletion of the group, as there is no going back after you complete it. With this consideration in mind, after typing the name of the group, click on proceed to complete the deletion of the group.