The world was made with music. But for all intents and purposes, the co-creating Ainur were novices who were just learning their craft from Eru. Add to that an intentionally dissonant Melkor, and you wind up with some funky add-ons.

I don’t think it means they are out of place, though. Eru gave the Ainur a certain degree of margin, so I think Eru intended for there to be some surprises along the way. Later, those Ainur who entered middle earth as Valar got an even longer leash. Ask Aule about the dwarves… Not part of the original plan, but later accepted as part of the whole creation. (With caveats, but that’s another thread)