Seriously, if you've had your camera, lenses and accessories for more than a couple of years, why has at least some of it not given up the ghost?
Are you not pushing it hard enough? Are you not taking enough photographs to wear it out? Are your lenses pristine, without even a scratch on the protective UV filters?
Take a look at the shutter release button and the handgrip. Are they worn to a dull shine? How about that digital sensor? Take a shot at f/22 of a piece of white paper. How many blotches can you see?
It's a given that you don't have your camera with you all the time. Do you avoid changing lenses if you're in a dusty environment, if it's a bit windy or wet? Do you ever shoot near sand?
Have you ever held your camera out over water, a big drop or a forbidding hole to get that interesting angle? Have you ever waded into the sea, water filling your boots, crouched low and shot back at people on the beach?
Have you ever taken your camera out in the rain? Have you ever tossed your camera up in the air, facing down, on the self-timer, to do an aerial group shot?
How about your tripod. Are the legs sloppy and loose from too much use? Are the feet dirty and rusty from sitting too long in the mud and salt water?
How many feet have you snapped off your strobes? How many gels have blown away in the wind? How many lens caps have rolled into a drain? How many memory cards have you put through the wash?
How long has your gear been cosseted, wrapped in lovely soft camera bags, how long has it not been shooting?
If you 'aint broke it, you 'aint pushing it hard enough!
Now if only my 350d would hurry up and finish dying...