One of the most important financial goals for retirees is maximization of after-tax income. There are two ways to accomplish this: (a) maximize pre-tax income and (b) minimize income tax liability. A Roth IRA can go a long way toward helping you achieve the latter.
There are two ways to fund a Roth IRA: (a) annual contributions and (b) conversions. Annual contributions, in and of themselves, generally won't result in a significant source of retirement income due to the relatively low limitation – currently $5,500 or $6,500 if you're age 50 or older. In addition, eligibility to make Roth IRA contributions is limited to the extent that your income exceeds defined limits.