My wandering mind returned with a question niether it nor I could answer. Is it possible to "shoot out" or "wear out" a string but not have it fail? Will all strings either stretch excessively or break eventually, or can a string lose strength without stretching or failing catastrophically (e.g. loss of elasticity)?
If I read the question correctly, the answer is "no".
I find that my servings wear to thin long before the strings would ever wear out, but I do have my nocks perhaps fit a little to tight, and I have been filing my nocks out a bit at a time to try and solve that problem.