They donu2019t.If you earn no income. you donu2019t have to fill out a return.If you earn under a certain amount, you donu2019t have to fill out a return.If you earned money and had an adequate payroll deduction to earn a refund, you donu2019t have to fill out a return (you would however, forfeit your refund by doing so).Whether to file a return depends on your income, your situation and in some cases, whether you wish to collect a refund due to you.