The senior taking the mortgage has to decide if they need the money more than they want to leave it behind. They may not have much choice.
Other options, the family supports the person and they stay in the house, no reverse mortgage.
Move to senior facility under medicaid (good luck).
If the individual is capable, they make the decision. Couples generally want to stay in their house. After the death of one, it's a coin toss.
I would add, moving to a senior facility or in with the kids, frees up the house to generate rental income. I’m working with a client on that option now. She has fixed up her house nicely and can’t stand the thought of renters, but she needs to move and wants to pass the house along.