An attempt teaches more when its record is specific. Preserve what you tried, under which conditions and what happened. General statements such as it did not work leave the next version with little guidance.
For a fictional resource launch, record the audience reached, the page shown, the action requested and any observed response. If very few relevant people saw it, the result may say little about the resource's value. If people arrived but could not download it, the delivery problem needs attention first.
Separate layers of failure
Was the idea unsuitable, the execution incomplete or the evidence too limited? These explanations can coexist. Acknowledge the limit before deciding the whole direction is wrong.
Choose the next attempt to clarify the most consequential uncertainty. Repair a broken step before testing another headline. Ask a reader about confusing instructions before adding more promotion.
Preserve the comparison
Keep enough of the earlier version to understand what changed. Write the next prediction before seeing the result so the review cannot quietly move its target.
An unsuccessful attempt can still be valuable if it makes a better next decision possible. The value comes from examining the work honestly, including the parts that contradict the explanation you hoped to keep.