Two-way and one-way doors
Match decision effort to the consequences of going back.
Predict first
Before you read: predict
A tiny catalog export-field removal changes what external importers receive. The producer's old source branch still exists.
Which classification fits the stated commitment?
The 30-second version
Classify a decision by what returning would require, not by its code size or implementation effort. A retained compatible path can turn a format or field change into a two-way decision. Consequential choices that cannot practically be undone deserve more deliberation. This lesson classifies the commitment; deployment rollback rehearsal belongs to judgment-change-safety.
Match decision effort to the consequences of going back.
How it works
Step 1 of 6
Analogy: Removable and destructive furniture joints
A furniture maker considers a joint held with accessible removable screws and another joint whose removal, in this example, destroys the joined panels. The visible joint can be equally small in both cases. What changes is the consequence of taking it apart. The maker can trial a removable assembly, inspect it and reassemble the original. The destructive assembly deserves more thought before joining valuable finished parts.
| Stated furniture condition | Decision property |
|---|---|
| Accessible removable fastening | Available return path |
| Removal destroys the panels | Irrecoverable consequence |
| Keeping the original fittings | Preserved compatibility option |
| Actually disassembling the trial | Evidence about undo |
This is not a universal claim about glue, screws or furniture safety. Some bonded joints can be released; some screws become inaccessible. The stated conditions determine this example. Likewise, software labels such as adapter or rollback do not settle reversibility. The design must preserve the behavior and state needed after returning. The analogy stops before distributed coordination, where different versions can interact and a transition itself can fail. [S2]
A reversible decision still needs judgment. A small qualified group can understand the exposure, choose, observe and correct. It does not follow that every reversible change should bypass ownership or basic review. Conversely, requiring a large permanent committee for every easy-to-reverse experiment can slow learning. Bezos describes different decision processes for different consequences, not a blanket preference for either speed or bureaucracy. [S1]
Try it
Answer first, then check. Nothing is saved.
Question 1 of 5
A catalog presentation trial retains the old assets and a configuration switch, and writes no consumer-visible record while active.
Which process fits the supplied facts?
Question 2 of 5
A public record representation must change while consumers update at different times.
Which plan preserves a practical way back?
Question 3 of 5
A catalog cleanup deletes its stored client-label mappings after adoption. Consumer records still contain labels from 365 days ago; the producer's replay history covers 7 days. Its source archive contains code, without the deleted mapping rows.
Which process fits the proposed commitment?
Question 4 of 5
A catalog renderer trial originally retained its old assets. A later proposal removes the archive and keeps the same ticket label.
Which review revision follows if the return consequence has changed?
Question 5 of 5
One catalog change takes six engineer-days but keeps an exit path; another short edit erases the sole reference required to return.
Which commitment merits the more deliberate process?
Go deeper
Pro tip
Authored documentation habit: write the decision's scope beside its owner so a future reviewer can tell which commitment the record describes.
Related lessons
Checked against the tools and docs as of 2026-09-30.