This note is a part of my Zettelkasten. What is below might not be complete or accurate. It
is also likely to change often.
This is not, of course, valid for biological entities. This is more relevant to non-perishable things like ideas, music, technology and systems.
If a book has been in print for forty years, I can expect it to be in print for another forty years. But, and that is the main difference, if it survives another decade, then it will be expected to be in print another fifty years. This, simply, as a rule, tells you why things that have been around for a long time are not "aging" like persons, but "aging" in reverse. Every year that passes without extinction doubles the additional life expectancy. This is an indicator of some robustness. The robustness of an item is proportional to its life! -Nassim Taleb
The longer technologies have survived, the longer they are likely to stay alive. This is called the Lindy effect.
An idea or system that has lasted 1000s of years is likely to outlast an idea that has just sprung up. This is something to think about when considering what is Sustainable and what is not. Something that is old is more likely to be sustainable than something that is new.
This phenomenon is beyond value judgement. Social norms like caste-based discrimination are slow to change and so is adoption of toilets.
Think of a normal curve. We are most likely to be in the middle of the lifecycle of an an idea than its beginning or the end.