The Perishable Instrument
A new engineer's confusion is the only direct measurement you'll ever get of how legible your system actually is. It's also a reading that expires in about three weeks, and most teams spend those weeks destroying it.
Documentation
The Runbook Gap
A runbook written the day after an incident captures what you wish you'd known. A runbook written six months later captures what you remember. The gap between those two is where the operational knowledge goes.
Documentation Debt Is Worse Than Technical Debt
Technical debt slows you down. Documentation debt actively misleads you. One costs time. The other costs trust.
TODO as Breadcrumbs
Why well-placed TODO comments are some of the most valuable documentation a codebase can have