Activating and Deactivating Custom Roles

You cannot delete a custom role, instead you must set its activity status to Inactive. To change a custom role's activity status all you have to do is click the Status toggle marked below and click Save in the top-right corner.

Figure 1 - Settings, Custom Roles, the Custom Role activity status

References:

About Security Roles and Permissions
Creating Custom Roles
Modifying Custom Roles