A dive mask with a low volume design traps less air inside compared to one with a high volume. The air inside the dive mask will impact your buoyancy as it wants to drag you to the surface. Having a low profile mask also makes it easy to clear the mask. This might overall not have a significant impact on most recreational divers. Using a low volume design mask does become a real issue if you're freediving. That doesn't mean that high volume masks are worse than low volume design masks. They have one significant advantage. The larger volume variants provide a better peripheral vision and feel a little less cramped. With a low volume design mask that is easy to clear, you do have the lenses sitting very close to your eyes. That does allow you to clear out any water much, but it also can be an issue if you are claustrophobic in any way! Most modern scuba diving masks feature a low volume design.