There could be several reasons why the front brakes on the driver side are worn out while those on the passenger side are still new. Let's explore some possible causes:

1. Driving Habits: One of the most common reasons for uneven brake wear is the driver's habits. If the driver frequently applies the brakes harder or more frequently when turning left, it can lead to increased wear on the driver side. This can happen, for example, during left turns at intersections or roundabouts.

2. Weight Distribution: Another factor to consider is the weight distribution of the vehicle. If there is a significant weight imbalance between the driver and passenger sides, it can cause uneven brake wear. For instance, if the driver often travels alone and carries heavy loads on the driver side, it can put more strain on the brakes on that side.

3. Mechanical Issues: It's also possible that there are mechanical issues with the braking system itself. For example, a sticking caliper on the driver side could cause the brakes to constantly engage, leading to premature wear. Similarly, a malfunctioning brake pad or rotor on the driver side could cause uneven wear.

4. Road Conditions: The condition of the roads can also contribute to uneven brake wear. If the driver frequently encounters steep inclines or descents on the driver side, it can put more strain on the brakes and cause them to wear out faster.

5. Maintenance Neglect: Lastly, improper brake maintenance can also result in uneven wear. If the driver neglects regular brake inspections, cleaning, and lubrication, it can lead to accelerated wear on one side.

It's important to note that these are just potential causes, and a thorough inspection by a qualified mechanic is necessary to determine the exact reason for the uneven brake wear. They can examine the braking system, check for any mechanical issues, and provide a more accurate diagnosis.

References:

• YourMechanic: What Causes Brake Rotors to Wear Out?
• AA1Car: Brake Wear, Causes and Prevention
• Haynes: Why Do My Brakes Wear Out Faster on One Side?