What is the purpose of mirrored memory regions in NES’s CPU memory map?

I’ve started reading the “official” NES Documentation and in page ten, it says that “memory locations $0000-$07FF are mirrored three times at $0800-$1FFF”. My question is, what is the purpose of this mirroring? Wouldn’t it make more sense to use that space for other purposes or just to increase the number of available resources in a very limited hardware?

I’ve started reading the “official” NES Documentation and in page ten, it says that “memory locations $0000-$07FF are mirrored three times at $0800-$1FFF”. My question is, what is the purpose of this mirroring? Wouldn’t it make more sense to use that space for other purposes or just to increase the number of available resources in a very limited hardware?

I’ve searched over the Internet and maybe it could be for compatibility between devices from the same family or improving redundancy in case of data loss, in which case, shouldn’t it be enough with just one mirroring instead of three?

Thanks for any answer you can provide.