Removing debris from your gravel is a critical function of maintaining your tank. It not only keeps your gravel looking great, it helps remove a lot of matter from the gravel that can be toxic to your tank, with nasties like nitrates and ammonia, which potentially can be harmful for your fish.
Clean gravel keeps your tank looking great
Helps remove all of those debris that can cause issues if they accumulate too much
Excellent way to do a water change at the same time as cleaning your gravel.
Generally can be done while keeping your hands dry.