The algorithm at the end:

  Start -> Open Folder -> End

In reality, natural language uses synonyms that often start with different letters. So without numbers, I still need to scan every directory one by one.

With numbers, I assign categories according to the phase of a process in which the item occurs. For example,

  1 plans
    |- A first draft
    |- B Lisa's notes
    `- C design
  2 analysis
    |- A exploratory
    `- B design implementation
  3 deliverables
    |- A May 2023 report
    |- B June 2023 presentation
    `- C August 2023 report

I can limit my search to folders and items that are in the low/medium/high range, according to what I am looking for. But alphabetically sorted, this directory structure would look much more ad hoc:

  analysis
    |- design implementation
    `- exploratory
  deliverables
    |- August 2023 report
    |- June 2023 presentation
    `- May 2023 report
  plans
    |- Lisa's notes
    |- design
    `- first draft