A security incident is inevitable for two reasons:
Those two realities make it inevitable that a security incident of some sort will happen. Think about this:
Read this article on how a CEO and his organization had $400K stolen from their account using a combination of hacking and spearfishing. This hack was smart and creative. The hackers were patient and used sophisticated social engineering while the organization had weak controls.
We all have to take Cyber Security seriously, together.