What is why we decided?

Why we decided is a concept in personal epistemology: Recording the context of a decision prevents future confusion about why you made it. Without a written record of the forces, constraints, and reasoning at the moment of choice, your future self — and everyone else — will reconstruct a fiction and call it memory.

Example: A software team inherits a codebase that routes all database queries through a single connection pool limited to five connections. The new developers find this baffling — the database can handle hundreds of concurrent connections. They spend two weeks refactoring the pooling layer to remove the "bottleneck." The system immediately crashes under load. Three escalation calls later, a former team member explains: the original database server had a licensing restriction that capped concurrent connections at five. The pool limit was not a mistake. It was a deliberate architectural decision made to prevent license violations that would have shut down the entire production system. The constraint had been removed when the company migrated to a new license two years ago, but nobody recorded why the pool limit existed in the first place. Two weeks of engineering time, a production outage, and a licensing near-miss — all because the context of the original decision was never written down. Had the team maintained an Architecture Decision Record stating "We limit the pool to five connections because our database license caps concurrent connections at five; revisit when the license changes," the refactoring would have taken thirty minutes of verification instead of two weeks of archaeology.

This concept is part of Phase 9 (Context Sensitivity) in the How to Think curriculum, which builds the epistemic infrastructure for context sensitivity.