Grip is essential to cycling in that it allows you to corner confidently and faster, and it transfers your power to the terrain more efficiently. Losing grip happens because of a couple different scenarios. One, if your tire comes off the ground, your wheel has nothing to grip and you lose contact with the surface. Two, the friction of the surface changes, for example, if you’ve walked on ice, you know you have less grip than walking on pavement.
How does a deep section gravel wheel help you grip? That’s a good question. As we learned in reason 1, above, a deep section rim absorbs vibration when it acts like a leaf spring. This not only helps by reducing vibration above the leaf spring, but it also helps the wheel keep contact with the road surface since the bumps in the terrain are absorbed into the leaf spring. Keeping contact with the surface obviously helps with grip.
A good way to visualize this is to think about riding a mountain bike. First, think about riding a bike without shocks, you can probably feel how bumpy the ride is and may have even gotten some air on a couple bumps. Now, think about riding the same line with a bike that has shocks, the ride is much smoother and your wheels keep contact with the ground. So, you can think of deep section gravel wheels like shocks, allowing you to stay in contact with the surface and have better grip to maneuver the trail.