Human nature doesn't like things to change because they want truths to base their life on or support the beliefs that they have established. An evangelist of note in my parents circles was a man named Ray Comfort who liked to try and prove to people that they were sinners using "laws of nature" to demonstrate unavoidable truths like gravity, therefore "spiritual laws" like the Ten Commandments must also be true. While I'm not saying there isn't a higher power with a set of moral guidelines because I cannot prove it one way or the other, I am saying that seemingly everything we can measure in the universe is constantly changing.
Even in religion the original intentions of spiritual leaders become misconstrued over time or lose weight because of societal and technological changes. Many of the dietary laws that the Jews followed in the bible were because they didn't have the technology to preserve food or inoculate animals against parasites. The bible says "I am The Lord. I change not." yet the God in the Old Testament is a cranky vindictive bastard compared to the God in the New Testament.
If you can't adjust with the times, life will judge you and you'll experience what the detached hand wrote on the wall in Babylon "mene mene tekel upharsin" - you have been weighed in the balances and found wanting. Stay lose - stay relevant.