There is a persistent assumption that an unwritten recipe is a recipe at risk. The opposite is frequently true.
Written recipes freeze; remembered recipes adapt
A recipe committed to paper stops changing. It becomes a record of one cook's version on one day. A recipe held in memory keeps being adjusted — for what the market had, for who is eating, for how much time there is. It stays useful, and useful things get repeated.
Measurements live in the palm, not the cup. You learn by standing next to someone, not by reading what they wrote.
The transmission is physical
Watch a handover and you notice how little of it is verbal. The instruction is in the wrist, the sound the pot makes, the colour at which something is judged ready. This is why a written version so often disappoints the person who grew up with the dish: the document captured the ingredients and lost the method.
Where it actually breaks
The risk is not writing or not writing. It is the absence of the kitchen itself — migration, long commutes, households where nobody has three hours on a Sunday. When the occasion for cooking disappears, the recipe follows, whatever format it was stored in.
What preservation should mean
Less archiving, more occasion-making. A dish survives because people keep having reasons to cook it — which is why community food events, family gatherings and small food businesses do more for heritage than any recipe collection.