Lets equate this to a bunch of children given coloring books and a box of crayons. There are those that try to color as many pictures as possible, without worrying about if it looks right, or staying in the lines. When the book is full, they go home, or get a new one. Then there are those that follow every line, and make sure the sky is always blue, the grass is always green, and everything in between is right. They sometimes even lay out the crayons they will be using next to the book in the order they will be using them. Then there are those that purposefully ignore the lines. Not to mess up the picture, but to give it their own touch. All of these are the good kids. The ones that sit together and play. They will look at the way the others colored, and sometimes think it something they could use in their own pictures.
But then there are the bad kids. Sure, some of them may color great pictures, but they also expect everyone else’s pictures to be just as good, and match their own exactly. If everyone does not make the same drawing, with the same colors in the same places, these kids will throw a tantrum. Sometimes it is explosive, and they try to take everyone's colors away, and draw in others books. Others are more subtle. They offer to 'help' you. A little scribble here, a few lines there. Before you know it, you are sitting back as they fill in your book for you.
I have had dealings with both of the latter, and sent them both packing. It ok to guide those that wish to be guided, and show them where you think the right colors should go. But it is not ok to try to force this upon others. When someone (or a group of someones) do not follow your version of how things should be, there is two options. One, adapt. Any good roleplayer can do this. Two, move on. It is not your job to correct others. If it is very far off from what everyone else is doing, then a polite suggestion OOC in a /tell is the way, not trying to override a roleplay with your own.
(ps, I am one that ignores the lines at times, then holds my picture up for everyone to see.)