Others may not appreciate their belongings being ordered chronologically, alphabetically, thematically, by a colour-coded system or otherwise.
Personally, I don't understand this one. Why not? I'm only trying to help. Who in their right mind doesn't like having their possessions in an order that makes their stuff easily found and accessible? It makes absolutely no sense to me so I'm sorry if I rearrange your bookcase or CD/DVD collection, but I swear I am genuinely trying to help you. As well as the fact that unordered belongings make me feel incredibly uncomfortable.
But looking at it from the flip side, I get very unsettled when someone tries to rearrange my stuff when I have it in a specific order, so I suppose it makes sense that others may not like their stuff being reordered. Of course, there are people who don't mind it or actually welcome it. However, seeing as I can never read people and will never be able the two apart, I'm not even sure why I made that point. Eesh.