---
title: Explanation
description: Why the practice works the way it does.
---

These pages explain the ideas behind the practice. Read them in this order.

1. [How it fits](/explanation/how-it-fits): the three places the practice lives, and how a rule changes.
2. [The quality funnel](/explanation/quality-funnel): catch each mistake as high as you can.
3. [The life of a program](/explanation/life-of-a-program): one program from the plan to the hand over.
4. [Model selection](/explanation/model-selection): how each worker's model is chosen.
5. [Context economics](/explanation/context-economics): where the tokens go.
6. [Framework evidence](/explanation/framework-evidence): what the practice caught, what it cost, and how the next period is measured.
7. [The watcher](/explanation/the-watcher): how one timer keeps a long session going while nobody watches it.
8. [The archive](/explanation/archive): what the practice no longer runs, and why.