Veidt asked the precognitive being if his plans for utopia would come to be, and if it was all worth it in the end. Osterman cryptically responded by saying “Nothing ever ends”, and teleported away leaving Veidt once again in doubt as to whether or not his plan was successful.
From what I understood, he spent the whole story acting super-sure about what would happen if he did nothing, and how he alone could fix it. But in the end of the comic, this showed he had doubts. Veidt didnt have precognition, just very good prediction. But also an over-inflated ego. He killed a lot of people for a “maybe”.