I have a retirement plan equivalent to 401k. But, I know many people who work until they die. One of my coworker came back to work after his retirement from the previous job. He had 401k and enough money to enjoy, but he said that he got bored sitting at home. Thats why he came back to work. Another example are parents. I don't think they will ever retire although they have enough money.

You need something to do after work if you want to enjoy your retirement. Thats why I would like to build a lake house and buy a boat.