There are a lot of factors that play into the timing of when you should start thinking about changing your stings and cables. More than anything, how much you shoot plays the biggest part. The strings and cables are put through a lot of stress during each shot you take. This repeated stress on the strings shot after shot can take a toll on your strings over the course of a year. Depending on which bow I am talking about, my target bow or my hunting bow depends on when I change my strings and cables.