“There are other worlds than these”
Traditionally, in stories modeled after the Hero’s Journey, the main character receives a call to action, which he or she initially resists. Take, for example, Bilbo Baggins, who is cajoled out of his comfortable, quiet life to go on an adventure by Gandalf. In Stephen King’s fantasy stories, the characters are self-motivated. No one has to urge Jack Sawyer to light out for the Territories—he has a good reason to embark on a perilous journey. Similarly, Roland Deschain chooses his mission to find and save the Dark Tower, even though it will take him on a wild journey for the rest of his natural days. No one conscripts him. (Although, to be fair, sometimes his characters are yanked into a quest without being given any choice in the matter.)
In Fairy Tale, Charlie McGee Reade also decides for himself to go on a magical adventure although, when he sets out, he has no idea what dangers he will face and what will be asked of him while he attempts to achieve his goal.