The Hero's Journey is an important narrative device that frames a story. During the beginning of many games, there is an inciting incident where a village may be burned to the ground, or the would-be hero learns of a prophecy they are destined to fulfil. This is the "Call to Adventure".
However, just because a hero gets the opportunity to save the world, there are some that should have stayed at home, had a cup of tea and waited for the troubles to go away.
Sometimes the decisions that these heroes make is with the best of intentions, but thinking about them for just a minute or two would spare everyone a headache. But then there are the world-class morons, those that are selfish and won't stop at nothing until they get what they want.
And even if they achieve their goal, what then? Of course it gets worse, and if they had thought about it for a few minutes they might have worked that one out for themselves.