I think Zira,nuka,vitani,kovu & all the outlanders where hunting for
food on scar's orders during the battle

i dont think the producers made him up yet

This is just My theory, But I think when Scar saw that Nuka
was not going to grow into a strong Lion. He had Kovu
cupnaped from another Pride and chose Him to be the next
King

hi, i wrote this question , and i think it might be because
Nuka wasn't responsible enough to be king. And hed get
killed anyway.

That's a good question. Maybe someone could write a fanfic
about it.

I think its because Kovu was the last born and so chosen to
be king.