Countless Americans look forward to retirement and the flexible lifestyle it tends to offer. Unfortunately, a large number of workers might never get there. In a TD Ameritrade study, 25% of U.S. adults say they don't think they'll ever retire. And they're probably not the only ones. That's because 1 out of every 3 workers have no money set aside for the future, and that includes 30% of folks 55 and over.But even those who are saving aren't doing a good enough job.