Let's say you have a child. We'll call him Billy. Because of your schedule, you and your working spouse/partner decide that it's time to hire a nanny to help with childcare.
You hire someone who seems very nice. She promises to do a lot of things that you think will be good for your child – no TV allowed, an hour of reading time every day, outdoor activities, healthy snacks, and so on. This sounds promising, so much so that you don't even feel as guilty about leaving Billy in the care of a virtual stranger.
After a few months you realize that not everything has gone as well as you hoped. The nanny isn't bad per se, but she's not following through on some of the promises. She gives him more snacks than you would like. She arranges playdates with the children of adults you don't know. Billy seems to have picked up a few four-letter words from her. It's a lot of small things, not one big thing. But Billy bonded with the nanny and you don't want to fire her.
So you hire another person to help care for your child – a 47 year old schizophrenic convicted sex offender named Rich Crenshaw who keeps three knives on his person at all times. He promises to straighten that nanny right out.
Almost immediately you realize that things are not quite right. Billy seems to have a lot of unexplained cuts and bruises. He reverts to sucking his thumb and gently sobbing himself to sleep. The nanny has stopped doing the things you disliked, but it seems like she stopped doing the things you liked as well. She's sort of a non-entity.
You have a little sit down with Rich and the nanny, letting them know that you don't want Billy to be given snacks but you don't want him to be starved. You don't want him playing with strangers, but that doesn't mean he should be locked in the closet. You want him to behave, but you don't want him threatened with a knife. In your mind these are reasonable demands.
Rich pulls out his knife, grabs your child, and runs into the attic. He holds the knife to Billy's throat and insists that he'll ventilate the little SOB unless you let him do whatever he wants. After a tense standoff you figure that it's better for Billy to be messed up than dead, so you negotiate.
Clearly the right thing for Billy lies somewhere between the two approaches. Neither the nanny nor Mr. Crenshaw did the right thing, so you realize that both are at fault. You work out a compromise: your child will get healthy snacks and outdoor playtime in the morning, and then in the afternoon Rich will beat him with a broken table leg, slash at him with a broken Night Train bottle, and dangle him from the roof.
Deep down you're not happy. You know that this isn't exactly "good" for your child. You feel indirectly responsible for this situation but you can't quite figure out what you did wrong. Isn't moderation good? Splitting the difference between opposing viewpoints? Finding balance? But try as you might, you just cannot understand how things went so wrong. When you hired that knife-wielding 47 year old schizophrenic convicted sex offender, you trusted that he would do the right thing. Instead he turned out to be crap-eating crazy, precipitated a hostage crisis, and acted like some kind of violent sociopath.
It truly is an outcome that could not be foreseen.