Well, we all know what happens when we assume. So rather than assume we know what Jesus' motive was, let's see what he actually said about it. John 9:2-3 (NRSV) gives us the answer:
Did Christ say that his love for the Jews was the reason he was to restore this man's sight?As he walked along, he saw a man blind from birth. His disciples asked him, “Rabbi, who sinned, this man or his parents, that he was born blind?” Jesus answered, “Neither this man nor his parents sinned; he was born blind so that God’s works might be revealed in him. ...