You turn 65. A helpful person explains that you can have a Medicare Advantage plan with a $0 premium that includes dental, vision, hearing and a gym membership, or you can have Original Medicare plus a Medigap policy that costs a few hundred dollars every month and covers none of that.
Put like that, it is not a choice. It is a no brainer.
Here is what nobody says in that conversation.
Going from Original Medicare to Medicare Advantage is a door you can walk through at any time. Coming back the other way, with a Medigap policy, may require an insurance company to approve your health first. In most states, they are allowed to say no.
That asymmetry is the most consequential thing about the decision, and it is barely mentioned in any advertisement.
Today we look at it honestly, because both options are legitimate and the trap is not choosing Advantage. The trap is choosing it without knowing the door locks behind you.