If we're not careful, we can easily fall victim to pushy sales tactics to buy expensive annuities. Annuities and other life insurance products are often sold using your fears against you. There is a tendency for annuities to be oversold because of the handsome commissions paid to sell them.
To be clear, there are times when an annuity might make sense, but many retirees have other guaranteed income sources like Social Security. There are various annuities (fixed, single premium, deferred, etc.), so it can get confusing.