Why Is the Vision So Weak?

He was stabbed with a blade from behind that made him weaker. Corvus Glaive's staff disrupts his ability to function and his atoms were not be able to fully restore. That's why he was not able to fight back. That staff is able to slice through any known thing and person in the universe.

Why is Vision so weak Marvel?

After being taken by surprise and stabbed, Vision is largely useless in the battle and is only saved thanks to the arrival of Captain America and his friends. In Wakanda, Vision did manage to kill Glaive but was swiftly relieved of his Mind Stone and destroyed by Thanos.

Why does Vision seem so weak in Infinity War?

So Visions weakness was his mind. His disbelief in himself was causing the power of the stone to be hindered enough to where he was able to be stabbed, and not phase. His head was cluttered with so much negativity, that it caused him to give up his existence and be willing to die.