Why Does CLass Builder force KEY property?

When I build a collection ABC of Class XYZ using class builder it forces the first property of Class XYZ to be "KEY as Variant".

Why?

Then when I add a class to the collection I must add two keys, the first internal to the class and the second as a key for the collection.

ABC.add Key, blah, blah, sKey

Thanks for ay clarification.

illini_dill