manufacturers strive for higher velocities(regular loads versus +P loads),but they have safety and liability constraints,why can't us handloaders do what the ammo manufacturers won't/can't do.
the 38sp evolved into the 357m to attain higher velocities with those bullet weights of the 38sp(notice I said weight not design),the 357sig pushes 9mm projectiles faster than a 9mm factory load can,the 357max goes beyond the 357m.It's a constant evolvement to increase velocity.I load 88/90 380 bullets into 9mm(same bullet dia).
Hydrostatic effect(larger cavities in gelatin tests,tissue destruction in simulated flesh/body tests) increases as velocity increases.
Rifle cartridges are also evolving along the same lines,there's always a cartridge that comes along to speed up a bullet.