Itachi knew it was sick and wrong to want to die by his brother's hand. But Itachi had always been able to see the bigger picture. The massacre of his clan was only a small part. All for Sasuke, in the end, really. Itachi thought Sasuke should experience the pride of knowing he had avenged his clan, even if it comes at the price of his beloved brother, Itachi's, death.
One night, Itachi wondered what it would be like to hear Sasuke scream his name. Would Sasuke cry when things worked out the way Itachi had planned? For some reason, Itachi found Sasuke's tears fascinating rather than disgusting. For Itachi, Sasuke's tears were a confirmation that Sasuke was weak, but Itachi would make him strong. Once Itachi was gone, Sasuke would never have to cry. Itachi didn't stop to think that once he is gone, Sasuke might not smile again either. Itachi forgot that, yes, he was the one to make Sasuke cry, but he was also the one who made Sasuke's smile shine brighter than a white flame.