I will use an example from someone who I don't much like and am really happy to not have to work with any more. We will call her X., rather than use her actual first initial, because there are days when anonymity may not be enough!
When T. was 4 or perhaps 5, he was in preschool. Then, as now, he has a lot of spare physical energy and needs ways to express it. It is the hyperactivity characteristic of a lot of ADD diagnoses but now known to not always be present in the disorder. I think of it as motor restlessness: "ants in your pants", "can't sit still". Etc. He liked to walk around in circles along a few sidewalks at his preschool, and one winter day, that suddenly became Not Allowed and he and I were freaking out about it because it was after school and he didn't want to head home yet. We were on the bike (because I couldn't get him to leave his seat belt on in the car) and you can't make a kid ride on a bike if they don't want to. Anyway. X was insisting we leave and T. not walk on those sidewalks, a new, unexplained rule. And after some discussion between me and X. about T. and rules, X. said, "Well, he won't be able to go to any school if he can't follow the rules."
Which was just ridiculous and also a violation of FAPE, IDEA, etc. I eventually got the kid home, but it took a while and we wound up involved in a really unpleasant interaction with a woman in a car who couldn't understand why I was walking a kid and a bike (also pretty dangerous -- it was a parking lot -- but we'd been kicked out of the safe place to be in motion and this was the safest route home). I was spitting mad and talked to the director of the preschool and the ABA head and possibly someone else -- definitely those two. A couple of things turned up. First, earlier in the day in a completely unrelated incident, a child had slipped on ice on the sidewalk and hit her head, precipitating a trip to the hospital and widespread fear and panic. Did anyone _tell_ me about this? No. They just freaked out, made up an arbitrary and ridiculous rule, and _did not show the work_ that had generated this rule.
Show your work.
If I had known about the accident, I could have addressed the underlying fear. We could have collaboratively problem-solved a way for T. to be physically active in the quiet, car free precincts of the administration building where the preschool is located and not trigger this fear of slipping on the ice. But since I didn't know about the incident, I couldn't do anything about that fear.
Second, the aide in question honestly had no idea what the next placement would be for T. if the school district preschool was unable to meet his needs. And honestly, they did not do a great job meeting his needs, altho they did a lot better than kindergarten did the next year. Halfway through kindergarten, the consensus that T. couldn't be helped in the school district was unanimous (I didn't even have to say anything!) and the special ed coordinator for the district found out what the next placement short of a private placement would be and proposed it. I thought, okay, this is the next hoop to go through before ending up at Nashoba Learning Group or New England Center so, "Sure!" we'll jump through that hoop and maybe it will work and if it doesn't well everyone will agree about the private placement and we won't have to argue with anybody.
I was annoyed that my district seemed unable to come up with any information about the proposed placement (like, not even a printed piece of paper -- I had to find the website myself). I asked around and the placement had a Rep. But, shrug, gotta do the work. Placement was _awesome_. There has been some teacher turnover, which is a bummer, but T. has steadily improved and steadily become happier and all is good. So I circled back to everyone who said anything negative or just had no idea and told them. Because that is part of having the knowledge to do better next time. Rep is undeserved. Rep is probably a historical artifact. Etc. The experience for the next crop of kids who were having trouble meeting the rules of the district schools was really different: they had staff at the preschool who knew the name of the next placement choice and could refer them to a mother of a child in that placement to talk to about details (that would be me). By showing the process, the next placement happened in kindergarten instead of first grade, and everyone was happier and less stressed.
When we cannot explain how we get from point A to point B, it's entirely possible that somewhere in there, we failed to see a choice, we failed to recognize we _made_ a choice, and that failure meant we had a worse outcome than was inevitable.
Usually, showing your work is something that conjures up long division, or listing sources for Birth, Marriage, Death dates in a family tree. But showing your work -- knowing the process, recognizes each choice you make _as you make it_, knowing what data went into the decisions, _knowing where we didn't have data to make decisions_, are things that happen every day for the rest of our lives. Showing our work can help us understand why we have the friends we have, why we have the family we have, why our kids are thriving (or not), why we find our lives satisfactory (or not) and even why we feel the way we feel.
It is a royal pain in the fundament.
ETA: If you are still hung up on me stating that it was ridiculous that a kid wouldn't be able to go to school just because they couldn't follow the rules, and mentioning Tourette's doesn't resolve that tension for you, here's another way to think about it. Let's say the rule is that before you can start learning/being taught, you have to "show you are ready" by sitting still facing the desk. This is a pretty typical preschool/kindergarten compliance measure, widely understood as "necessary" and obviously at odds with a variety of low-incidence medical conditions and thus cannot truly be a reason to not educate someone. In T.'s case, the motor restlessness makes the sitting still tough, and the autism makes the eye contact component of the rule difficult (eye contact is used by a lot of neurotypical classrooms as a proxy for shared attention, and let's just note that this is ridiculous and move on). X. saying that inability to follow the rules = can't go to any school crystallized a realization in me. "If you can teach a kid to read, do math, and learn about history and science while the kid is jumping on a trampoline, then sitting still is Not a Requirement." Since it is trivially true (NOT SHOWING MY WORK HERE! IRONY!) that you _can_ teach a kid to read, do math and learn about history and science while the kid jumps, sitting still really cannot be a requirement and anyone who says it is has failed to show the work of why the rule is valid -- federal law says the rule _isn't_ valid -- and this is a perfect example of why you should remember how you got to where you are, however you feel about that place.