Healthy people with good genes that have relatives who are mentally fit up to thier last days. And people who think that all the money being dumpped into longevity by billionaires will increase the amount of time people in general can maintain a decent quality of life. And then me, who is curious about how the world changes over long periods of time and just wants to be there to see it. And maybe see a breakthrough that somehow keeps us alive even longer. Death is so final.