The idea is to separate the permissions between custom forms and custom fields, to allow people to create forms, but not create new fields.
We hold the governance of new custom fields at a Global admin Level, which means we have to create all forms as well. This makes sure that our group admins in every agency and market in our global network do not end up creating 100s of duplicate fields (either in language or slightly different naming for the same data etc etc) in our single instance. As this would 1 make a mess of the system and 2 break global reporting.
We need to be able to allow our group admins to only be able to create new custom forms, and not create new custom fields.