Why should you never depend solely on your mirrors when preparing to change lanes?

• Mirrors do not need to be adjusted.
• Mirrors can show a complete view of all areas around your vehicle.
• Even correctly adjusted mirrors leave "blind spots" where vehicles may not be visible.
  Explanation:

  "Never rely solely on your mirrors when preparing to change lanes, as even properly adjusted mirrors have 'blind spots' behind both sides of your vehicle. If a vehicle is in the blind spot, it may not be visible in your mirrors. Always make a quick over-the-shoulder check before changing lanes or passing."
• Mirrors can show the distance between you and the vehicle behind.