This assignment was probably made with the expectation that he would be able to control the Iga clan, which was an element of power basis of the Ise-Heishi (Taira clan) including TAIRA no Kiyomori.
平清盛ら伊勢平氏の権力基盤の一部であった伊賀を抑える役割を期待されての人事と思われる。