When you get to heaven, you will understand ALL things and know that God's love, justice and judgement are perfect. We are way too carnal and imperfect to begin to understand so many things of an infinite and divine nature.
Its like trying to figure out how God could always exist, never having a beginning or ending. Impossible to understand on this plane.
I will say this, nobody will ignorantly go to "hell", whatever that is. See, even the nature of hell is a mystery. Some people say a burning fire, some say eternal darkness, some say non-existance. Again, just know Jesus died for YOU, and let God take care of everyone else, trusting everything in the end will end up exactly where it was meant to end up based on perfect judgement, not our imperfect preception of judgement.