Someone tell me why?!

Why are there even sequels to the first movie? In the first movie the war was ended, it was over, there was no more to be discussed! Then the crappy second movie came out, then the "ok" third installment came out, and I finally thought they ended the whole thing. They need to stop ruining the memory of such a great movie!

"Bear suits are funny- bears as well." - Walken
"We're not sheep." -Edward