What I’ve seen break first isn’t code correctness, but the loss of decision context, why the system looks the way it does today. That context usually lives in old PRs, commit messages, and informal conversations rather than in the code itself.
Documentation helps, but static docs decay quickly. Social knowledge helps, but it’s fragile. The hard problem is preserving intent and architectural reasoning as the code evolves, without slowing teams down.
I’m curious whether people have found practical ways to do that at scale.
Anything less is a very poor substitute at best.
IOW you can rake in the bucks a lot of other ways, outperform your wildest expectations and be perfectly satisfied financially, but you're really quite poor by comparison to how rich you would be if you did it right from the beginning.