1. Driver Negligence/Blind Spot
Many drivers have difficulty spotting or noticing motorcyclists on the road.
"Approximately 70% of collisions are the result of the negligence of drivers."
2. Poor Road Conditions
Many collisions occur "due to the presence of curbs, debris, potholes, bumps or even roadside barriers" when a rider tries to avoid an accident. These are the accidents that have caused severe lower body and spinal damage, and sometimes even brain damage.
3. Speed Disparities
Accidents don't always occur because of speeding, but can also occur as a result of going too slowly, compared to traffic flow around the rider. These accidents manifest as rear-ending or being rear-ended.
4. Other Factors
- Climbing skill of the driver
- Drunk driving
- Undivided roads
- Aggressive driving/recklessness
- Old bikes or old bike parts
Source: Used Motorcycle Review