Two things affect how high your gun shoots - how far the center of the pattern impacts above the gun's point of aim (if you were shooting it like a rifle looking along the surface of the rib).
One is the slope of the rib. Guns designed for trap shooting slope down toward the muzzle, which causes the gun to shoot a few inches high at 35 yards.
The other thing is your eye's distance above the surface of the rib. The higher your eye is above the rib, the higher your gun will shoot. When a shooter sees space between the beads, the gun will shoot higher than if the beads were stacked in a figure-8 pattern. (The eye is slightly above the level of the rib.)
Shooters want their guns to shoot high so the pattern will impact above the gun's point if aim. This allows shooting with the target always remaining visible and avoid having to cover the target with the muzzle to provide the vertical lead required to break it.
The choice of how high shooters want their guns to shoot involves their swing speed to the target and the distance to the target when it's shot; some shooters shoot targets much nearer the house when they are rising faster and want higher shooting guns for that reason.
You will need to experiment to find what works best for you. The way to alter your gun's vertical point of impact (POI) is to vary the height of your comb . The higher the comb (your eye) the higher will be the gun's POI.
To have the same POI from one shot to the next, a consistent gun mount if required. This is achieved only with practice mounting with an empty gun 10 -20 times a day for a couple of weeks. There is no other way to achieve it, and it's IMPORTANT.