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If we tested several alternative trees (as we recommended In The design phase: creating new trees in Chapter 3), we’re obviously keen to see which performed best (so we can pursue them) and which performed worst (so we can discard them).

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• Previous versions of the trees
  This is easily done by saving our old versions and making our changes to a new “current” copy of them. If we ever need to go back for an idea we previously discarded, it will be there waiting for us.
  
  
• Decisions and our rationale for them
  As we revise and reword individual items or entire sections of a tree, we can annotate them with our decisions and a brief rationale (where needed). We can also use color-coding or text styling to distinguish items that were deleted, changed, or are placeholders for future content.
  ~ss
  
  In the example below, we've color-coded deleted item as red (some marked as "future" for later releases), and added rationale and instructions for other items:
  
  Image Added
  
  
  

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• If we change the tree, the location of correct answers may move (for example, FAQ was under Contact us, but is now under Support).
  Or, some correct answers may disappear (or new ones appear) because of our reshuffling of topics in the tree.
  
  
• If we change a task, the correct answers for it may also change.
  Minor tweaks of phrasing are unlikely to matter, but if we change the meaning or purpose of a task, we need to check that its marked answers are still correct and complete.
  
  
  

When we analyze individual tasks, especially low-scoring ones, it’s natural to want to fix the problems we discover. This usually means shuffling or rewording topics.

That’s all well and good, but we need to make sure that we’re making a change that will help the tree perform better in real-world use, not just for this single task.

•  example of over-tweaking a tree for a task

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If you’re If we’re considering a change to your our tree to fix a low-scoring task, we should make sure that youto:

• Review other tasks that visit that part of the tree, look at their results, and check that your our change won’t cause problems for them.
  
  
• Review other reasons that users may visit that part of the site; they may not have been important enough to become tasks in your our study, but they should still be supported by your the tree.

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Next: Cherrypicking and hybrid trees

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