“There has been a change in curriculum!” Dumbledore said, “Everyone will be resorted at the beginning of each year!”

Imagine it, personalities and ideals are pretty fluid so why not make the house system fluid? It’d be like playing for a different team every year, getting what you want and need out of different houses! Maybe your failing and want to study more? Sounds pretty Ravenclaw to me! You want to make your parents proud, looks like we got a Hufflepuff here!

I can think of zero characters that wouldn’t benefit from walking in other peoples shoes.