If one of the most basic attributes to compelling storytelling is conflict, forces standing in opposition to the protagonist, this demands that the protagonist have a motivation or goal that can be challenged. A state, achievement, character or object that the protagonist is longing for, and which drives their decisions throughout the story, as conflict arises in the form of characters and obstacles keeping the protagonist from attaining them. What your main character wants, is the Object of Desire.
Tying the Object of Desire strongly to a character’s needs, so that they are driven in an authentic manner to pursue the Object, is invaluable, since it highlights the stakes and makes it clear to the audience that there is no turning away from this goal for the protagonist. This is why films where the heroes are motivated only by a desire to “save the world” are not nearly as satisfying as, say, low-stakes films which more clearly involve the characters and their inner conflict. Of Marvel’s recent output, there have been massively popular successes, and departures labelled as missteps. Why did audiences care less when the planet was on the chopping block in Eternals, then when their friendly neighbourhood Spider-Man had to leave his loved ones to put an end to the trouble caused by trying to do right by them?
It’s not always so simple, however. The Object of Desire can be unclear to your main character, and a popular technique of revitalizing the practice involves a contradiction between the external Object of Desire the character pursues and misunderstands to be their need, and their internal Object of Desire, which they often inadvertently attain, or only begin to pursue once they’ve realised their misguidedness.
Many McGuffins, which effect the plot but have no bearing on what the film is about at a character or thematic level, are external Objects of Desire. Most adventure films involve these, since they are tangible and apparently attainable treasures, artefacts or tombs the characters go in search of, driving the plot forward as ill-intentioned baddies race to plunder the object, but the heroes inevitably discover that the object was not what it seemed, the real treasure was whatever they gained through the experience, the baddies are quickly disposed of (often in ironic fashion, smelted by the Arc of the Covenant, walked off the plank of One-Eyed Willy’s pirate ship, hoisted by their own petard), que smooching between the attractive couple at the film’s centre, roll credits. Think of The Lost City, a modest hit in a bygone genre from this year which follows this model to a T, a simplicity audiences have responded to warmly as of late.
The Object of Desire is a fundamental consideration when writing a majority of stories, and one with the potential to improve the story as a whole, if seen for the significance it carries and retooled with this in mind. Neither you, nor your audience can ever be in doubt as to your protagonist’s Object of Desire, or else you risk sending them on an unsatisfying journey.