Quote Originally Posted by Tvtyrant View Post
Morality works differently in LotR then in modern conception. It is corruptive, so committing small acts of evil lead the doer into larger and larger acts. It is why small time crooks and bandits so easily fall into full throated supporters of universal enslavement in setting, because the tipping point came when they chose to steal a piggy bank 20 years ago and everything naturally progressed from there.

Melkor making bad music wasn't exceptionally evil, it is was the choice to do it at all that seals his fate. This comes up later with the Elves, Gollum, etc. Once the initial choice is made it is all but impossible to stop the corruption from spreading.
I think that's too bleak a reading, while evil is corruptive, we have several examples of characters committing evil acts but remaining on the side of the angels, so to speak.

Spoiler
Show
The people of the Houses of Finarfin and Fingolfin who take part in the First Kinslaying remain heroes. Elu Thingol betters himself by overcoming his prejudice against Men. Tùrin remaining a good guy of sort despite all the killing he's done.

And we all remember Boromir, right?