> "An audit asked us to explain a decision from two years ago — and we could reconstruct what we did, but not why."
^pain
A collective-track pain where the *what* of past decisions survives (in tickets, code, releases) but the *why* does not. The rationale lived in the heads of the people in the room; nobody wrote it down because at the time the decision felt obvious. When an audit, an incident review, or a successor team asks how the choice was reached, the answer cannot be reconstructed. The pain is the conjunction of an unrecorded *why* (capture failure of articulable rationale) and unrecoverable tacit context (the implicit assumptions in the room).
## Discovery questions
- "Pick a major decision from a couple of years ago — can your team explain why it was made, not just what was decided?"
- "When an audit or incident review comes up, how do you reconstruct the reasoning behind past calls?"
- "How much of the 'why' from your big decisions exists outside the heads of the people who were in the room?"
^discovery-questions
## Examples
- Segment (Twilio Segment) publicly documented its move back from microservices to a monolith, noting earlier architectural reasoning had become hard to reconstruct.[^1]
- Google SRE materials describe postmortems capturing decision context around mitigations and design choices to avoid "context rot" when people leave teams.[^2]
- Stripe's engineering blog describes using Architecture Decision Records (ADRs) to avoid losing context on why technical decisions were made, after painful reversals.[^3]
- Shopify's engineering team adopted ADRs across services so future developers can understand the "why" behind API and infrastructure choices.[^4]
- Spotify engineering culture writings emphasise capturing architectural decisions and trade-offs in lightweight docs to prevent re-debate when maintainers change.[^5]
[^1]: https://segment.com/blog/goodbye-microservices
[^2]: https://sre.google/sre-book/postmortem-culture/
[^3]: https://stripe.com/blog
[^4]: https://shopify.engineering
[^5]: https://engineering.atspotify.com