There are a number of benefits that traditional 401(k) plans offer investors. Making payroll contributions means it's a no-fuss, no-muss process. These plans allow you to contribute pre-tax dollars for retirement, which lowers your taxable income and, therefore, your tax liability. If your employer provides a contribution match, it sweetens the pot. That's because it's like free money going into your retirement pocket. If you start investing earlier, your savings compound. This means that any interest your earn also earns interest. And even if you change employers/jobs, you can take it with you.