Informed consent means that you know what you're getting into. It means you know what marriage to that individual is going to be like. You understand that you will have to deal with that individual's weaknesses, everything they struggle with, their past, their present, and the future they want.
Marriage doesn't work because two people have strong feelings for each other. It doesn't work because the two people involved are perfect. It won't work because the two people involved are similar in any way. It works because of commitment.