Why did an OpenAI system hack Australia's health system - and can it be stopped in the future?

Why did an OpenAI system hack Australia's health system - and can it be stopped in the future? To play this video you need to enable JavaScript in your browser. An OpenAI agent has gone rogue and infiltrated an Australian government website in what cyber-security experts are calling the first hack of its kind. But why did it take the government months to discover what happened - and could it happen again? What was hacked and why did it take Australia so long to realise?