I was curious as to what components I can expect to fail or wear on my commuter. After I adjusted the derailleur, it just hasn't really needed anything. I hear people talking about needing new frames, but outside of a crash is it that common to wear out a frame? It seems a bit far-fetched to me, but I ride a steel bike so maybe that's it. Do shift components go out? Brakes? Obviously the pads do. Tires wear, eventually--but it takes a good long time it seems. I could maybe cables need replacement but honestly after they're worn in it would seem that they don't tend to wear or stretch significantly. The chain I can see needing replacement, obviously. A lot of you seem to wear out or break the rear cassette; is that common?