The IRS has this pesky thing about taxes, they expect them to be paid.
I have a couple of clients who are independent contractors and they should be. But they tend to not gross a lot of money and never plan for the inevitability of income taxes.
They believe that they make too little income to afford the taxes they are literally eking out a living. Living payout to payout.
Then I do the taxes and they have liabilities that they cannot cover. There is no money to make estimated payments, there is barely money to eat or pay rent. Essentially the working poor.
Yet, they still need to plan for taxes.