Like others have said, it depends on the quality of the string as well as how much you shoot. I shoot about 600 arrows a week year round (hoyt defiant) and i got about a year out of my first factory set. At that point, the servings started to separate making quite a bit of variability in my shots...especially at longer distances. Check to make sure your servings are all good (especially where the string comes off the cam...it is common to get separation in this area with lower quality strings). I have been shooting a first lite string for over a year now and there is no sign of wear or tear. Its always important to wax your string as well. Every couple of weeks or if the string starts to feel "dry". For the cost, new strings and cables do make a very big difference in repetition and accuracy. You will see your groups get way better instantly.