Is anyone familiar with the term "life tolerance of a resistor" ? I could not find a good read in google. Any link with the explanation will be sufficient.
"Life tolerance" is undefined.
Likely it means the long term variability of certain parameters associated with that resistor. But we are really guessing here, as the original question isn't clear.
I think life tolerance is the tolerance a resistor can have during its whole life. A resistor can change its value because of different reasons like temperature or age. Therefore the life tolerance is the maximum tolerance of the resistor the manufacturer guarantees. I'm not really sure if this answer is 100% correct but I think you could understand it better.