Hiring cheap human labor in the US costs (for minimum wage) $36 to $40k per year.

So according to [1] spot costs 1 year of a decent-wage employee or 2 years of a minimum wage employee. And of course that's disregarding that spot will happily pull nighttime duty, work on weekends, Christmas, and will happily walk into a chemical plant risking his life for you ...

[1] https://beebole.com/blog/how-to-calculate-the-real-cost-of-a...