Then when Judas, who had betrayed Him, saw that He had been condemned, he felt remorse and returned the thirty pieces of silver to the chief priests and elders, saying, “I have sinned by betraying innocent blood.” But they said, “What is that to us? See to that yourself!” (Matthew 27:3-4)
A pastor once pointed out his belief that Judas, believing the Christ was coming to deliver Israel from Roman rule and set up His eternal Kingdom on earth, potentially believed betraying Him would force His hand to finally move, bringing his expectation to pass. False understanding, false assumptions, false hopes often lead us to go against the better judgment of conscience. Those who benefit by that to gain their desire can care less when our conscience kicks in and we suffer a type of buyers remorse.
Conscience has a purpose that protects us from bad decisions. Listen to it early, so grief of sin is avoided.