Rear-end collisions happen for many reasons, one of which is falling asleep behind the wheel. When you drive at night, you need to take the time to get enough rest. If you begin to get tired, then you need to pull over and stop instead of putting yourself or others in danger. If you don't, you could cause a collision like this one.
While people often claim that a rear-end collision is always the fault of the rear vehicle, that simply is not the case. Did you know that the first driver in a line, someone who merges into a line or others could be at fault as well? It's the reality that every situation is different, so the rear driver can't always be blamed.