This is the sentence I am trying to understand:
Context: They are talking about recycling
I understand the meaning, which would roughly be: My mother made this with clothes that were not needed. My question is, why is it using that verb conjugation: いらない+なる=いらなくなった (to become not needed).
Am I missing some nuance in the translation? Why is the sentence written in this way and would this be incorrect or unnatural?: