Improving over time.
WHAT ITERATION MEANS
Changing, measuring, and changing again.
WHAT TO ESTABLISH BEFORE CHANGING
The current position, measured.
WHAT TO CHANGE
One meaningful thing at a time, where possible.
WHY
So you know what caused any difference.
WHAT TO MEASURE
Task completion Time Errors Abandonment
HOW LONG TO WAIT
Long enough to exceed normal variation.
WHAT TO DO IF IT IS WORSE
Revert, and record why.
WHAT TO DO IF IT IS UNCLEAR
Say so. Unclear is a legitimate result.
WHAT TO AVOID
Redesigning everything at once Changing based on one person's opinion Assuming a newer design is better because it is newer
WHAT TO RECORD
What you changed, what you expected, and what happened.
WHY
It prevents repeating experiments, and it shows which judgements were sound.
WHAT TO REVIEW
Whether the original problem was actually solved.
