Ok, let me clarify a bit more. When you put the mess in the litter box, and show the kitten that this is where the messes go, don’t do so in a disciplinary manner. Merely show the kitten that the litterbox is where to do it’s business. It’s not “punishing” it’s teaching. Sometimes it takes the kitten actually seeing/smelling one of it’s messes in the litter box for it to catch on that this is where “society” wants it to go every time it needs to do so.
Also, I wasn’t the one who said one method was better than another here first, you were. I merely mentioned A method that I’ve personally found works to finally get through to a kitten and litter train it.
Yes, you are correct, actual “discipline” (Whether it’s a "No’, or shaking a pop can filled with pennies, or a spray etc.) should only be used if the feline is “caught in the act” of doing wrong.
I’ll further add, that the only time I resorted to a mother cat’s “shaking” method, I did not to injure the kitten and did it because this kitten would not stop chewing an electrical cord, despite having lots of other things more palatable, and despite being sprayed, “No’d”, “noise bombed” etc. The “mama cat” method actually got through to it. (It was weaned too early, it’s mom rejected the whole litter too soon, so it didn’t get the learning period it needed with it’s feline mom.)
It wasn’t even intentional, I was pretty frightened, and shaking with worry for the kitty because I saw that it had actually gotten almost clear through the casing, I’d caught it in the act, picked it up, showed it the cord, and “No’d” it, but I ended up also shaking it a bit too I was so wound up. I was shaking like a leaf, nearly passed out when I saw it chomping away merrily, and in tears with relief that it didn’t get electrocuted. (I was quite a bit younger, and more high strung and apt to really worry a lot at the time.) Maybe it was seeing me so worried that worked, and not the unintentional shaking it got?
I was holding it with both hands, supporting its weight properly. (One hand under the hind paws to help it feel safe and support it’s weight.) I later read that mother cats will shake their kits to displine them if they are being unruly. I’d never do that to a larger cat, because I don’t want to hurt them, just reprimand them for a social wrong.