Fantasy
The best fantasy rules are often the ones nobody bothers to name.
People bow, avert their eyes, leave a door unlatched, refuse to speak a certain title. Not because a wizard issued regulations, but because habit, fear and class pressure have done the work already. That feels more believable than a world where every custom arrives with a footnote.
Once a rule becomes too tidy, it starts to look invented. The messier version is usually better. Somebody obeys because their grandmother did. Somebody else because they know what happens if they don’t. Only later does it get dressed up as law.
People bow, avert their eyes, leave a door unlatched, refuse to speak a certain title. Not because a wizard issued regulations, but because habit, fear and class pressure have done the work already. That feels more believable than a world where every custom arrives with a footnote.
Once a rule becomes too tidy, it starts to look invented. The messier version is usually better. Somebody obeys because their grandmother did. Somebody else because they know what happens if they don’t. Only later does it get dressed up as law.
Sometimes the unnamed rule is only unnamed because the writer hasn’t done the awkward bit yet. If a custom matters, somebody eventually has to explain why it exists, or the story starts feeling like it’s hiding the plumbing. A little mess is fine. Total vagueness just reads like the author hoping we won’t ask.