This is because in all circumstance a ski jump increases safety, increases performance,
How much kinetic energy does an aircraft gain by using a "ski jump"?
...increases ability to handle ship pitch motion and reduces pilot handling workload.
Please explain those statements in more detail.
However to use a ski jump you do need the aircraft to be fitted with an attitude control system that is effective at speeds below normal wing stall speeds.
So, when a Harrier I or II takes off using a "ski jump," relative wind over the main airfoil is "below normal wing stall speeds" shortly after the aircraft departs from the ramp?