Driving for many consecutive hours without resting can make **driving more dangerous** due to **lack of rest**. This is because the driver may experience **fatigue** and **drowsiness**, which negatively affect their ability to drive safely.

- **Fatigue**: When a driver is fatigued, they may have difficulty concentrating on the road, feel heavy-eyed, have poor vision, and experience a sensation of pressure in the head. Additionally, movements become slower, and there is greater difficulty in making decisions and reacting quickly. These symptoms increase the risk of accidents.

- **Drowsiness**: Drowsiness causes difficulty in keeping the head upright and the eyes open, blurred vision, and loss of concentration. It can also lead the driver to be easily distracted, drift out of their lane, or not pay attention to traffic signals. These factors increase the danger at the wheel.

Therefore, it is crucial to take regular breaks and rest adequately to avoid these symptoms and maintain driving safety.