Can some action be justifiable and at the same time be the incorrect or bad action ?

Yes.

One example is this: You are on the sidewalk and a man in a window points a gun at you. You yell for him to put the gun down, but he continues to point it at you and threaten your life. You don't want to be killed, so you shoot the man and he dies. Afterward, you find out that his gun wasn't real; it was a real-looking replica.

You were justified in shooting him because it appeared that he was about to shoot you. But the action turned out to be wrong, because he was not actually a danger to you at all. This was not your fault; it was the victim's fault for acting like he was about to kill you. Still, it is a tragedy. If you had known the gun was a mere replica, you would not have shot him.

Logic can be used to justify almost anything.