Cant speak for carbon, but saying that most bikes have a lifespan of 10 years is certainly not representative of the bikes I have owned. Parts wear out, but with reasonable care and "normal" use (no crashes etc) bikes ridden like mine with maybe 2-3000 km per year are just fine after 10 years of use. Im talking the frame, other stuff wears out and gets replaced.
You're doing it wrong. ;->