Generally speaking, your decision to receive lower benefits sooner will hinge substantially on your health expectations. If you are in good health, then you may have to plan for three decades (or more) of retirement! Though good health is anything but a certainty, you should not assume that your health will deteriorate early — unless you have good reason to believe it. If you live a long retired life, you are much more likely to benefit from waiting for a few years for your full retirement benefit.
Suppose, for example, that your total benefit is $500 per month, and the difference in your monthly benefit is $100 if you choose to receive your benefit early, at age 64, as opposed to receiving your full retirement benefit at age 65. If you have a three decades-long retirement, the difference in payments could add up to roughly $30,000 — accounting for the additional year of early payments, of course.