Shishu let his guard down when using KA on danzo. Although it's filler id still like to point it out.
From the anime we see Shishu Activate KA and danzo sat there pretending to be stuck. However! We then see danzo appear out of no where and begin to assault Shishu and took his eye. With this being said we can Agree that Shishu overconfidence in his jutsu was the reason he was defeated by Danzo. Had he kept his guard up after casting he would have been fine.
From the anime we see Shishu Activate KA and danzo sat there pretending to be stuck. However! We then see danzo appear out of no where and begin to assault Shishu and took his eye. With this being said we can Agree that Shishu overconfidence in his jutsu was the reason he was defeated by Danzo. Had he kept his guard up after casting he would have been fine.
