There is always less unskilled jobs than people willing to get them therefore the salary will go down to some minimal value if not regulated. For example there

There is always less unskilled jobs than people willing to get them therefore the salary will go down to some minimal value if not regulated. For example there are people who don't have to pay for an apartment and they can agree to work for $500/month and people who have to rent won't be able to compete with them.