HITL - the ultimate no-code approach?

All these no-code tools are amazing, but they come with their own limitations ("bots" aren't smart enough, support request can't be fully automated, etc). Hiring humans on the other hand is infinitely more flexible, though it comes with its own issues (sourcing, training, QA, they need to get paid, etc).

Does anyone have experience running their business with humans in the loop? For example, having MTurk/Upwork contractors respond to support requests, doing cold outreach, data cleaning, or bulk web research? I'm wondering what the biggest challenges might be with this approach, and how much overhead there would be.