If you own your own business and can ensure enough clients you can make good money. But this isn't exactly a default situation. And it comes with all of the ass

If you own your own business and can ensure enough clients you can make good money. But this isn't exactly a default situation. And it comes with all of the associated overhead for owning your own business. If you are a one-person show you'll also need to be available at weird times for emergencies or will lose clients because you aren't available on a weekend to deal with some issue. Plenty of people working in the trades are making modest salaries working for some builder or some company that serves industrial clients.