If Itachi wanted left sauske alive simply so he'd have enough drive to develop his sharingan just to harvest it later, why did'nt he spare more members of his clan. If you wanted to steal the eyes of a sharingan user would'nt you want more to choose from ? Anything could've happened to Sauske while he was on a mission. He could've died and Itachi would've lost his chance to gain the next level of sharingan. He should've left the strongest members of his clan alive just so they would come after him while developing their eyes. If one of them were to to die he'd still have more to pick from. Is there anyone out there that agrees with me ?