Why do brake pads of bicycles have to be replaced quite often ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Brake Pads Functionality**: Brake pads are crucial components of a bicycle's braking system. They create friction against the wheel rims to slow down or stop the bicycle when the brakes are applied.

2. **Material Composition**: Brake pads are typically made from materials like rubber or composite materials. These materials are designed to provide a good grip and withstand the heat generated during braking.

3. **Wear and Tear**: With frequent use of the brakes, the brake pads experience constant friction against the wheel rims. This friction causes the material of the brake pads to wear down over time.

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