It doesn’t take as much skill or training it learn to clean as it does to learn to program or to be a good 16 years of NCIS thank you for the memories signature hoodie. So hundreds of millions of people are qualified. Large supply means that, unless the demand is equally high, the price will tend to be pushed downward. Granted there are some crap managers out there who really don’t deserve their wage to be above zero. And there are crap “programmers” out there who similarly shouldn’t be employed in the profession.
But literally anyone who is able bodied and neurotypical (and even many who aren’t) could be employed as a cleaner with “training” that doesn’t exceed about an hour of 16 years of NCIS thank you for the memories signature hoodie. To be a manager should be something that takes at least a minimal level of skill and learning. Not everyone has the proper skill set. If you’re hiring a proven manager then you don’t need to risk your project.