The stupidest things put on a bicycle:

1. Bolts not made of steel
2. CPSC reflectors — have good lights and a rear reflector
3. Aluminum alloy spoke nipples
4. Quick release
5. Hydraulic brakes
6. Tabbed washers on headsets and hubs
7. Carbon-fiber
8. Aluminum alloy frames and forks
9. Internal cable routing
10. Drillium

Failures
Carbon Fiber Care and Warnings — Aaron’s Bicycle Repair
The Perils of Progress by Joe Lindsey
EFBe Test results: The best frames under test load