welcome!
and i disagree. evil can be construed before the fact, can be anticipated. hypothetically, if george w. bush. decided to round up all the muslims in the u.s. and put them in internment camps, that would be evil, correct? yet it has not happened yet, correct?
therefore, while you're correct that evil/good have no meaning without someone to judge them, all moral actions can be judged from the moment they're conceived, not just after they're completely finished.