a convex has greater durability over a flat or hollow ground edge, but cannot attain the maximum sharpness of a hollow grind.

practically speaking, most production knives are ground with an edge more obtuse than the convex grinds we apply at home, so there's really no loss. also, grinding a hollow ground edge to the sharpest level attainable is unrealistic since steel ground that thin will not have the rigidity to withstand real use.