That's why secret societies were born to protect the valuable 10% of skills that did work exceptionally well, and were hard to rediscover by on your own.

Eh, even my grandmother used to do absolutely delicious pumpkin empanadas that none of my aunts managed to replicate. Might be local flour, the way of cooking the pumpkin, unusual spices, specific dough fermentation, her stove, who knows?

She decided not to share the whole recipe, even if she likely learned it from her mother, probably because it was a source of income.