They don’t last forever!
Whether brake or gear cable, whether you have visibly fraying ends or not, what you can’t see is the deterioration where the cable and nipple meet – the gradually developing dampness inside the housing that sets in and starts the metal oxidation process. Rust is the result. Rusty metal is metal ready to fatigue.
When you pull that brake, or more commonly because the cable is thinner, change that gear and the cable separates from its nipple – that’s it. And if the nipple gets jammed in the shifter it can turn from a simple and inexpensive ‘general bike servicing’ issue to a pricey ‘replacement shifter’ scenario.
Sometimes, just the quickest, cheapest, simplest things keep cycling life turning smoothly.
Replace your cables at least annually – regardless of your mileage