Under capitalism, it’s not enough for a person to be able to make a living providing a good or service to society. They need to be able to make enough to pay the people that do it for them, plus a profit for the owners. Without that profit, owners have no reason to make a corp to provide the good or service, so it doesn’t happen, or if it did happen, it gets sold to someone who thinks they can either turn it around or get more than they paid for it by liquidating everything.

But this means that there’s pretty much a whole economy available for people to provide those goods and services without giving a profit cut, meaning they can both undercut the for-profit corps doing it while making more than the corps would be willing to pay them.

Think about this any time you see something about a failing company, because it doesn’t mean you can’t make a living doing that thing, but just that you can’t make enough to cover loan costs (which can also be a big factor since business schools like to preach leveraging to the max) and still profit afterwards, after paying all of the workers.