playing as different Adc champs

Its odd you think having higher attack damage would let you get more kills cause you hit harder, but oddly when i play miss fortune i build like straight up attack speed with the bork combo and she just shreds people, end game i have around 2:20 attack speed with 290 attack damage, but i get more kills with attack speed builds then i do with attack damage build, strange no?

As i see it if an attack with crit around 500 damage hits a person 6x times, must be stronger then a person that hits with 1000 damage 2x, cause the more attacks you are pumping out in contrast to theirs you would also be healing more so then they are, cause with a bork I get a bloodthirster, and i figured out that 1 item with lifesteal is never cutting it any more but once you have 2 items giving lifesteal you actually see the effect that comes from lifesteal actually doing what its supposed to do.