According to the information Lumiaire intercepted, humans of this era haven't given up their resistance. A man named John Connor organized a resistance army and successfully destroyed one of Skynet's bases. Therefore, Skynet regards him as the savior of humanity and a massive threat, so it constructed a time machine in an attempt to send a robot back to the past to kill John's mother. The idea is that without her, the savior would not be born, eliminating the threat.
It goes without saying that after hearing Lumiaire's report, Duanmu Huai's first thought was - What kind of idiotic artificial intelligence is this?
What makes Skynet think that eliminating one person can prevent humanity's threat?
Is it out of its mind?
It just shows that artificial stupidity is just that, assigning order only to visible threats. Clearly, it only saw John lead the resistance army to destroy its base and considered him the biggest threat.
But what if there were no John Connor?