Why aren't all enumerations shown in the full types list?

I just realized there are a lot of enumerations which aren't shown in
http://schema.org/docs/full.html.

Take http://schema.org/MedicalSpecialty or
http://schema.org/ItemAvailability for example. they have a list of
enumeration members that aren't showing in the full types list.

Any reason why, doesn't it make them hard to be discovered?