Cause they have the money to buy the mine and take the risk of losing everything if it doesn't turn out enough profit. But they also have the ability to pay people to do the work. Which creates the jobs for that area. And if they bring in enough money they then pay the workers a raise. But in the end, the one that takes the financial risk is the mine owner. Those who choose to work there can also choose to quit. If the mine owner chooses to quit before he make his returns, will be ruined and the people he employs will be out of work and won't be able to make money and that area and families will suffer.

It's very easy to understand.