As observed by someone who is now in between young and elderly.
Elderly people tend to care about saving their money, while young people tend to be more wasteful with their money. Elderly people tend to regret not saving more when they were younger. The odds of living to an elderly age are heavily in our favor and the odds of being able to work (or wanting to work) as an elderly person are heavily against us.
Elderly people tend to think about their health every day. Young people tend to take their health for granted and assume it will always be fine. But if you live long enough, eventually you will have to deal with a serious heath issue. And how you live in your younger years will have some impact on what that issue will be and how soon it will happen.
Elderly people tend to appreciate the people in their life more. Young people tend to sacrifice relationships for career goals and recreational activity. And young people seldom consider that their friends, family, or co-workers will one day be gone, while the elderly have already experienced such loses and think about it a lot.
Elderly people tend to be humble. They tend not to be as protective of their ego as young people are. Young people tend to worry a lot about what other people think of them. In general, elderly people have lost too much to be egotistical — life has humbled them and they tend to be more able to empathize with others, because they have been through a lot themselves.
Elderly people tend to be more spiritually minded than young people. Young people tend to think very little about life after death. Young people tend to live as though how they live is not important as long as they get what they want. Elderly people tend to understand that how you live is more important than what you gain for yourself.