Board Thread:Theories and Speculation/@comment-26005711-20150719134117/@comment-25626003-20150719160911

Itachi's loss is what shaped Sasuke into the being what he became, and long before he even acquired the Rinnegan he had his mind up to attempt to reshape the world in a way he sees fit.....using Rinne Tensei at that point in time would've defeated the purpose. It makes sense.