Nearly 30% of millennials believe they will never retire, according to TD Ameritrade's 2018 Millennials and Money Survey. With stagnant wages and the soaring costs of education, health care and housing that they've experienced in their lifetimes — not to mention coming of age in one of the worst economic recessions in U.S. history — many are putting off saving for a time they're not sure will come as they struggle to make ends meet in their current daily lives.

While saving for a retirement you're not sure will happen might seem pointless, Erin Lowry, author of "Broke Millennial Takes on Investing," says it can actually provide younger generations with the stability and financial confidence they crave.