There are some things that need clarification before this:

Time does not exist, it is a construct of human mind. Human behavior changes over time because *evolution* not because *time*.

Ok, so: as humans age, they develop their cognitive functions and they become masters of being themselves. What you could say is that age defines behavior.

Also, time settles in some aspects like: when you first tasted a banana maybe you didn’t really like it. Over time, you tried bananas many time and eventually decided that you like them. Same for long term relationships.

With getting old comes boldness/recklessness, meaning that at some point, you have lived long enough to not care anymore about petty stuff. And that’s when “what if” happens: what if I buy an expensive car? What if I divorce and go rogue! What if I sell everything and move to a tropical island?

Anyway, bottom line is that it’s not time per se but age/evolution that affects behavior.