They never break, because they were designed that way.
You could use one to hang off the edge of a cliff, and it won’t give way under your weight.
When it comes to seat belts, no car manufacturer or passenger is willing to compromise on the material used.
We’ll never say, "Yes, I want to save money here. Please use a Velcro rubber band instead, or, whatever you have available that day in the factory."
When things break down in your business, there’s usually a compromise made earlier on.