Why does hierarchy design fail?

The most common reason hierarchy design fails: Treating your hierarchy as sacred architecture instead of working scaffolding. You'll know you've fallen into this when you spend more time debating where something 'belongs' than engaging with the content itself. The second failure mode is the opposite: restructuring compulsively, chasing the perfect taxonomy instead of letting awkwardness accumulate to the point where the right restructure becomes obvious.

The fix: Open your primary knowledge system — notes app, vault, project folders, whatever you use. Find one category that has become a dumping ground: too many items, too many 'sort of fits here' entries, or subcategories that overlap. Write down three alternative ways you could split or restructure that single node. Pick the one that eliminates the most exceptions. Execute the restructure now — move the items, rename the folders, update the links. Time yourself. It will take less time than you expect.

The underlying principle is straightforward: When your hierarchy becomes awkward restructure it rather than forcing things to fit.