Week 9 Worked Example: Iteration
Design Change Log
| Changed | Evidence | Why | Result | Worked? |
|---|---|---|---|---|
| Added card strip to each edge | Both testers let end tools slide | Stop tools slipping out | Tools stayed put for both retesters | Yes |
| Swapped ribbon tie for elastic loop and button | Tie slow and fiddly for both | Faster one-hand fastening | Fastened in about 4 seconds | Yes |
| Kept deep pockets unchanged | Both testers liked them | Protect what works | Still holds tools well | Yes |
Before And After
Before: curling edges, ribbon tie, tools sliding. After: stiffened edges, elastic-and-button fastening, tools secure. (In your submission, attach a side-by-side photo of yours.)
New Issue Logged For Week 10
The card strip makes the mat slightly harder to roll tightly. Carried forward to finishing to try a thinner, more flexible stiffener.
Why This Passes
- Every change traces to a specific test result.
- The working pockets were kept, not redesigned.
- Each change was retested, not assumed.
- A side effect was honestly logged for finishing.
Weak Versus Strong
Weak
"I remade the whole thing to look nicer." No link to evidence, working parts thrown away, no retest, no log.
Strong
Two evidence-driven changes, each retested and logged, working parts protected, and a new side effect recorded.