If Maiar who served Morgoth were corrupted into Balrogs, then why is it that Sauron, who is also a Maia and servant of Morgoth, didn’t become a Balrog when he pledged his loyalty to Morgoth?

Sauron was Morgoth’s most loyal servant and hand-picked heir, but while more famous than his master, Morgoth was even more powerful. Morgoth crafted his own Iron Crown in the volcanic mountains ...

In the Amazon Prime series adaptation of J.R.R. Tolkien's The Lord of the Rings, The Rings of Power, Galadriel is one of the most pivotal characters.