Laeserin on Nostr: With the plumber example, the problem is that it's a trade that provides direct, ...

With the plumber example, the problem is that it's a trade that provides direct, on-premesis labor, so it's very difficult to scale up and reduce the cost of labor per item, unlike a production line.

The labor is always almost all of the cost and you can only cut the marginal cost per-instance, by increasing the productivity of the laborer. That can be effective, but not nearly as effective as, for instance, off-shoring initial production steps for a factory, or streamlining vast automation.