I'm a former archaeologist, so my personal definition of technology is extremely expansive.

You don't actually need to nixtamalize maize. It's totally edible without and most americans today don't eat nixtamalized corn outside masa. It's just a process to make it more nutritious and importantly, nearly nutritionally complete. For ancient societies, nixtamalizing had a role similar to things like vaccination do for us today. It reduced malnutrition and the economic/social/political effects of disease. The difference I'm trying to highlight is that it probably wasn't understood as such and intentionally done for that purpose. Nixtamalization was culturally encoded as just what you did. Had they had a better understanding of nutrition, they probably would have made more intentional efforts to include the missing vitamins nixtamalization doesn't provide. We often see signs of those missing nutrients in precolumbian skeletons.

This extends to a surprisingly wide variety of ancient technology. Most metallurgy probably wasn't understood in the technical sense we think of it today until quite late. We see that with early glass, where people simply didn't understand what they were doing. Ingredients from specific areas would have specific effects, but sometimes didn't for reasons no one at the time understood. Craft communities would standardize on very specific, ritualized processes that simply couldn't be changed because they didn't have a good mechanistic understanding of the variables involved. One of the downstream effects of this is that poaching craftspeople is a viable strategy (they had the specific "recipe") and also that resources like sand from specific areas in syria and egypt were effectively non-fungible for centuries. You had to trade with whoever controlled that area even if you had the craftspeople.

Craftsmen having secret recipes isn’t quite restricted to the past. According to my drummer friends, nobody knew how to make cymbals as good as Zildjian’s until very, very recently.

A lot of tradecraft is in the most literal sense tradition, passed from one person to another with no other context than 'it works' and 'this is the way it is done'. The analogies in the software world are probably libraries, design patterns and languages. Each of these embody a lot of knowledge without being - usually - very explicit about the reasons why they are the way they are.

Researching those reasons requires a lot of work and most people just want to get to the result step without necessarily understanding why you put the oil in the pan before the egg. They're hungry.

Andrew Carnegie wrote that one of the things that gave him an advantage over other steel manufacturers was that he hired a chemist to test ore for iron content.

By implication, this was something that had never been done before.