The issue is with the nature of agentic systems and how often they run, a .001 failure is still huge. Attackers monitor their attack chances and use the most successful attacks so the actual success on the attackers side is much closer to 1 than .001.

This is the problem, this isn't a 'failure' mode where something randomly goes wrong, like a person accidentally sticking their hand in a machine. This is war where you are under active attack and the attackers adapt quickly.

Because of the breadth of LLM capabilities they have a nearly unbound attack surface. You spend so much of your effort making sure your prompt is secure that you either massively increase costs, or you partially lobotomize your agent making it less capable.

Solutions for these problems will have to come inside the model itself because both the attackers and models are far more capable than you on doing dumb/evil shit. Until the model itself can go "hey, wait a darn minute" a new fun way of encoding the attack can always be found.