I'll give a dialectical perspective here. I believe that all of these "good" and "evil" things are more of a matter of perspective. Ones reality is greatly influenced by their perception, and we see reality as we are, not as it is. So that being said, when we are practicing DBT we don't utilize the terms good, evil, bad, and what not. We say "effective" and "non-effective," as it takes the perception out of it, and bases the moment on the facts of reality instead of our own opinion.
DBT answer aside, I'd look at this like the mother who had amazing intentions, raising her child giving it everything she could because she loved him or her so much it hurt. Protected them from every potential harm that would come their way. And now the child ends up being "spoiled," mean to others, thinking that they are better than everyone else and intentionally lashes out because of a superiority complex, or maybe because they never learned how to social interact with others when they were being sheltered. Just like the knights said earlier, her intentions were good, but it led to an "non-effective" result. So I guess good intentions can create evil or bad outcomes, but i'd also say that those evil outcomes can have the opportunity to change as well. If we set something up to be good or bad, eventually the pendulum will swing and it will become the opposite. Hence why walking a middle path is so important, so that way we don't set ourselves up to suffer with the "pendulum" effect.
-David
