We like to wishfully think of human systems (software, government, anything) as immune systems that accumulate knowledge in the system itself over time so that it's increasingly resilient to the systemic problems it's encountered before.

Instead, human systems require eternal vigilance from the humans inside it. Even governmental systems which can encode knowledge into laws rely on the eternal vigilance of judges, prosecutors, and defenders to utilize that knowledge.

So GGz if you're writing a new subsystem in an OS and you're expected to learn from mistakes a team of two people made in some subsystem 20 years ago that someone quietly patched.