Killstealing bastards..

Kill securing* [slayer-jinx-wink]

They killed kenny. Those bastards.

Some champions by default will have lower damage than other champions unless the first is very fed or the latter is very bad. A champion like fizz for example will always have less damage than the ADC or Mage unless he is very ahead. He doesn't have poke abilities and when he goes in, most of his damage is single target burst so his 2k on a target nets the kill while 2k for an adc may just mean he poked multiple enemy champions down in a stand off who then healed.

With the jax and gangplank comparison. Gangplank pokes a lot with his barrels and gets people down but doesn't necessarily kill them since they just disengage and heal or it's stand off siege situations. Jax finally goes in and does damage and it's party time because someone is usually going to die either way.