It's often given as the perfect solution where someone shares a house with a partner or spouse, wants partner to be able to live it it after their death, but for it ultimately to go to their children.
I've only seen it happen IRL twice and both times was a bit of a disaster and made everyone miserable.
One example, the children really begrudged the (in this case) step dad staying and delaying their inheritance, and made every effort to "persuade" him that it was in everyone's best interests for him to sell up, realease his share of capital and rent, which made him more determined to stay. It ended up with the people the deceased loved most hating each other, and making each other's lives miserable, when she'd tried to leave things good for everyone, albeit that the relationship had always been rocky.
In the other the step mother had spent decades running the deceased's home. He owned it 100% but she'd made it a home. It was her home too and he left provision so she could stay there for life. She'd also been very good to the DC, very much part of their immediate family, they'd have all said they loved each other.
However, once money was involved the children started wanting control of e.g. the maintenance of the house. She felt they were trying to prove she wasn't maintaining it adequately, so she'd have to leave (I don't know if that does happen?). They were definitely hoping she wouldn't live too long! Again. it made everyone miserable. The children, lost their father in their 30s but had to wait until they were almost retired themselves for their inheritance, by which time a very elderly lady was still "insisting" on living in "their" house which was becoming increasingly unsuitable for her.
So any success stories or ways to make it work better, especially where there's a disparity in age or health (life expectancy)?