I think you and NYREDs are talking about apples and oranges here. He's talking about chicks that, under regular circumstances, can't hatch on their own. You are talking about chicks that can't hatch because your kids won't stay away from the incubator and are getting too dried out. If they were...
You didn't necessarily mess up. Sometimes they just are not strong enough to hatch, or survive if they do hatch. I've tried a couple of times to "help", but have decided from now on to let nature take its course. I know that people do help and the chicks survive, and all is well, but that has...