Curved blades are often believed to cut better due to several reasons related to their design and mechanics:

1. Increased Contact: A curved blade increases the length of the cutting edge that comes into contact with the target. This extended contact allows for more continuous and sustained cutting action as the blade moves along the target's surface.
2. Concentrated Force: The curvature of the blade concentrates the force of the cut towards the point of contact. This concentration of force enhances the cutting power and facilitates the penetration of the target, making it easier to slice through materials.
3. Efficient Cutting Angle: The curve of the blade allows for a more efficient cutting angle. As the blade moves through a cutting motion, the curved shape enables a slicing action with a reduced contact area, reducing friction and making it easier to cut through the target.
4. Cutting Surface Alignment: A curved blade allows for better alignment of the cutting surface with the direction of the cut. This alignment helps distribute the force of the cut more evenly across the edge, minimizing resistance and allowing for smoother and more effective cuts.

It's important to note that while curved blades are often associated with better cutting performance, the specific design, quality, and sharpness of the blade, as well as the technique and skill of the user, also play significant roles in determining cutting effectiveness.

Different blade designs, such as straight blades or serrated edges, may be more suitable for specific cutting tasks depending on the materials and desired cutting action.