Evil is the absence of good. Good was there first and to have evil, one must have the good as a grading scale.
All babies were born good, like a white piece of paper. Then something happens and here are we today.
Just like a student who started out with an A grade can easily get an F but an F student who strive to upgrade to an A is a tougher task.
So being evil is easy. Being good requires much working and to sustainable of being good is even harder.
I can go on and on to why the evil folks seem to stick around and why the good die Young philosophy but that's too much thinking for one day.