The End of the Silmarilion(Spoilers) Morgoth's End

[Armetiel]

Then he was bound with the chain Angainor which he had worn aforetime, and his iron crown they beat into a collar for his neck, and his head was bowed upon his knees. And the two Silmarils which remainedd to Morgoth were taken from his crown, and they shone unsullied beneath the sky; and Eonwe took them, and guarded them.
Thus an end was made of the power of Angband in the North, and the evil realm was brought to naught

Was anyone else wholly disappointed at this end...it seemed to unravel so quickly (especially if you compare it to the Lord of the Rings, but for now, I am not)
But for some reason it reminded me of when I was still in school and writing a story for English. I would go to so much effort and spend so much time working up to the main battle, or to whatever it is that needs to be accomplished...and then look at the clock and realize that I have no time for a proper ending...and just rush it all off "And then they arrived at whereever it was they were trying to get to...and they destroyed the bad guy, and every one lived happily ever after, the end" after pages and pages of building up to that...

Anyways, I was just wondering, can someone make it more interesting for me? lol. I don't know why that line was such a downer for me, but can someone who like the line try to explain it in different terms so I can see what a good ending it really is lol?
(I know, an odd request, but I've read it a few times, and think I need to hear this from someone else's POV)