Edit (complete rewrite):
OK so I'm completely rephrasing the question.
Let's begin with declaring the concept in hand - A is an infinite, willing, creation force. A "wants" to create all the natural numbers. I'd like here to use the concept of ordinal numbers suggested in the comments, just to deny its use here - A is one complete set, it cannot "move" to a different set (by saying this I admit that I am not sure about the validness of this sentence, and I have zero experience with the set theory, only general guidelines).
Just for clarification first: the infinity of A is it's "will" to create, not the fact that it "wants" to create exactly the idea of all numbers. But, it cannot "change" its will.
Now, let's assume A was able to create all natural numbers (this, might be the invalid assumption I thought of at first. But, as I said, I think this won't exactly be assuming A reached what it "cannot" [according to the definition of infinity] reach, as I've said the infinity in A is its creation force and not the exact creation of numbers). If A created all numbers it can, the very creation force that moves it, the very will that enlivens it, won't have what to "want" anymore. Hence, it's will will be limited.