An incredible amount of time, energy and money gets put into stopping car accidents. New technology is invented for the sole purpose of lowering collision rates. Driver education programs focus heavily on accident prevention and avoidance.

But the accidents don’t stop. They take thousands of lives every year and lead to tens of thousands of injuries.

You have to brave those roads every single day as you commute to and from work. You see accidents at intersections, in opposing lanes and in parking lots. You have close calls when drivers cut you off or just barely stop at a light before rear-ending you.

Why can’t we get accidents under control? Below are five reasons they happen.

1. Human error

The best safety systems in the world can’t stop a driver from making mistakes. People are careless. They’re negligent. They crash simply because they make mistakes, something that’s been true since the first car hit the street.

2. Drunk driving

Even skilled, experienced drivers can crash when they’re under the influence. Yes, it’s illegal to drive while drunk, but it’s also common. A lot of people don’t arrange for rides home from the bar or don’t want to pay for a cab. They decide to chance it, thinking it’ll never happen to them.

3. Distractions

Distractions are plentiful. A cellphone rings. A passenger talks. A driver tries to eat or drink coffee. The GPS needs to get reset to a new location. The radio station goes out of range and needs changing. When drivers look away from the road, they don’t see other cars, traffic signals and avoidable hazards.

4. Tired drivers

A long day at the office leaves someone feeling drained. It’s been a week of late nights, but it’s finally over. Then, on the way home, that person nods off, drifts over the center line, and plows into your car while you’re also trying to commute home. As with drunk driving, tired drivers will often try to chance it, thinking there’s no real risk.

5. Mechanical issues

Drivers often forget about routine maintenance. They just assume the car should be fine as long as they keep putting gas in the tank. They don’t change the brake pads. They don’t check the fluid levels. They ignore all of those little rattling sounds. Eventually, the car breaks down in traffic and causes an accident.

As this list shows, your daily commute is full of dangers. You can’t always avoid them. You can follow traffic signals and drive defensively, and other drivers are going to make serious mistakes that put you in danger. You may even wind up in the hospital. When this happens, it’s critical to know all of the legal rights that you have.