End Times Signs The world has seen celestial signs,prophetic cue cards that sudden destruction comin

Knowing that Noah was a preacher proclaiming God's truth in some form to the people of his day and given his godly character, we can assume Noah preached about the approaching flood and the need to repent. Furthermore, offering the world such a warning would be in keeping with God's character, since God typically gives opportunity for repentance prior to His judgments.
Just like today people don't listen, so they will miss the boat also.