Falling is a skill like any other - the more you fall, the better you get at it.
I'm not saying falls are recommended for the elderly, or that they should take risks that can lead to falls - but luck, just like I'm anything in life, plays a role.
Some people can't afford to live like they're made of glass, with all the support a available for them to prevent such events.
If you're not a wealthy elderly, or if you don't have a family willing to take sacrifices, then your luck starts to drop A LOT.