Originally Posted by
Oneder
If it starts to slip or looks like garbage then replace it. Chain measurements are kind of silly if you are not a racer.
Well, if you are not a racer or also not a person who wants to replace chainrings and cassettes more often.
I first learned about chain wear by riding a mountain bike until the chain was so worn that it eventually just snapped. I'm sure there were signs of things not working as well as they should have long before then that I just didn't have the experience to recognize. By the time the chain snapped the cassette cogs that were used a lot, and the large chainring were so badly shark-toothed and worn that I ended up having to replace them too. I'm firmly in the camp that measuring chain wear and discarding a chain that has crossed some threshold is a good idea.