This means that when you're getting hit by Ion damage you'll only know that once your shield is down. Same goes for overdrive since it also does increased damage against shields.
At least those 2 effect should throw a warning on shield hits, the others are not needed.
Cannon shows push, pull, emp, and stop.
Damage beam shows all effects.
missile and damage pulse show push, pull, and stop.
https://youtu.be/WJYusaszffw