The idea of the MacGuffin was never intended to be, nor should it ever be, taken seriously.
Seriously. If anyone comes at you using the MacGuffin as an explanation for why something is the way it is in a story, do yourself a favor and run.
Run as fast as you can because that person has no idea what is really going on inside of a meaningful story and arguing with them will prove to be as daunting as proving to the Flat Earth Society that our planet is in fact, round.
But what about Hitchcock, maaaan? How could you possibly say anything bad about the master?!
True, it was Hitchcock who originally brought this ridiculous story concept to light but really, how often in life do you find masters of their artform who can describe exactly what it is they are doing? There is no doubt that Hitch believed in the MacGuffin, but there is also no doubt that in doing so he proved his lack of understanding in regards to the mechanics of story. Masters often don't understand what it is they do, they just do.
Hitchcock was an eclectic filmmaker, one given to nonsensical endings that often left the meaning of the film up to the audience. More often than not though, an author is not after this result. The drive to write is more often than not accompanied by a desire to say something meaningful. This is where the MacGuffin fails.
A quick look at the wikipedia entry for the MacGuffin reveals a common thread:
a plot element that catches the viewers' attention or drives the plot of a work of fiction. the specific nature of the MacGuffin is unimportant to the plot, and the MacGuffin can sometimes be ambiguous, completely undefined, generic or left open to interpretation Commonly, though not always, the MacGuffin is the central focus of the film in the first act, and later declines in importance as the struggles and motivations of characters play out. Sometimes the MacGuffin is even forgotten by the end of the film.
In other words, it's a meaningless concept. Even Hitchcock himself thought so:
It might be a Scottish name, taken from a story about two men in a train. One man says "What's that package up there in the baggage rack?", and the other answers "Oh that's a McGuffin". The first one asks "What's a McGuffin?". "Well", the other man says, "It's an apparatus for trapping lions in the Scottish Highlands". The first man says "But there are no lions in the Scottish Highlands", and the other one answers "Well, then that's no McGuffin!". So you see, a McGuffin is nothing at all.
That, coupled with the explanation that the term may have originated with Hitchcock's friend and screenwriter Angus MacPhail, and it quickly becomes apparent that the concept of the MacGuffin was, and always will be, a joke. It's a nonsensical term made up by two friends in a story meeting to help them get to page ten. Why anyone would attribute authority of story comprehension to a joke is simply ponderous.
On the other hand, if one wants to write something meaningless, the MacGuffin is your tool.
Defenders of the MacGuffin always point to Casablanca and the letters of transit. Their argument is that the drive to attain those letters simply starts the story off. They believe the letters' only purpose is to provide the catalyst or Inciting Incident of the piece and that eventually they fall away in importance to the story's message.
Nothing could be further from the truth.
In Casablanca problems exist because there are two letters of transit that have gone missing, letters of transit that Victor Laszlo was going to use to get to America. Everyone in Casablanca is concerned with these letters, and it is in fact their actions or lack of action towards these letters that argues the logical side of the author's message. Ugarte has (or had) his own nefarious plans for them, Laszlo and Ilsa want them, the refugees will do anything for them (even sleep with Renault if they have to), Strasser wants them returned, Ferrari offers to buy them, and so on. Everyone has their own selfish interests at heart when it comes to these letters and it is this selfishness that creates the problems in the world of Casablanca. Overcoming that selfishness is the key towards achieving the Story's Goal.
The letters of transit are not simply a plot device to get the ball rolling. They are, in fact, the Goal of the story and the reason why problems exist for everyone. Once Laszlo recovers them, the problems in the big picture story are resolved and the film is over.
Some will argue that Casablanca is not about letters of transit, but rather about the romantic relationship between Rick and Ilsa. The truth of the matter is that Casablanca is both a love story between Rick and Ilsa AND a story about a resistance leader trying to escape the Nazis. The former is the heart of the story, the latter is the head of the story (the logical argument). Both work in concert to create meaning. Both are responsible for why the film stands the test of time. Complete stories incorporate both head and heart into one meaningful statement giving us an opportunity to experience problems both from within, and from without.
You can't have the head without the heart and you can't have the heart without the head. Asserting that the head falls away in importance can only be argued by someone who doesn't have a head.
Story is universal. Because story is an argument and because we all have the same brains (more or less) between our ears, the mechanism to argue our points effectively is the same regardless of point of origin. Sure, there might be some noise due to cultural differences, but at the base of it all, the process is the same.
In Amelie the story starts off when young disassociated Amelie discovers a box of children's toys hidden behind the wall in her bathroom. MacGuffinees would have you believe that this discovery was simply a plot device to get the story started. They would also lead you to believe that, like the letters of transit, the box of toys had little to do with the rest of the story.
Once again, they would be dead wrong.
In Amelie problems exist because people have negatively evaluated their situation in life. The jealous ex-boyfriend with the cassette recorder, the unsuccessful writer, and the brow-beaten store clerk--each one of these characters is suffering because they're stuck with a negative assessment of their lot in life. Getting them to reevaluate their lives, and see things in a positive light is the Goal of the story, a Goal pursued by the protagonist of the story, Amelie.
So sparking the imagination of the original owner of the toy box is more than simply a "plot device," it is the first test, the first proof-of-concept that what Amelie wants to do, can be done. It is tied thematically with the issues facing every other character in the story. It also explains why, in the end, the scene of the toy box owner sharing a meal with his estranged daughter and grandson is buttressed up against the scene of the writer seeing his words posted in public. By re-evaluating their lives (through Amelie's influence) the characters in the story have overcome their own individual problems.
The box of toys has a significant place in the overall meaning of the story.
When the MacGuffin is used as prescribed, the result is a story disaster. While The Maltese Falcon certainly has an important part in the history of cinema, it has no place in the halls of lasting and meaningful storytelling. The story, simply put, is broken. Part of this can be ascribed to its use of the Maltese Falcon itself as the MacGuffin.
Unlike Casablanca, finding the Maltese Falcon is NOT the Story Goal. If it was, then once it is revealed to be a fake, the problems in the story would be resolved and the film would be over. This is not the case.
In fact, the story is not over until they solve the murder of Sam's partner. This is the real Goal of the story, one that is purused by the Protagonist of the piece, Sam. The quest for the falcon gets things going, but has little to do with where the film ends up. It's a perfect MacGuffin.
The Maltese Falcon, in sharp contrast to the children's box of toys in Amelie or the letters in Casablanca has absolutely nothing to do with the meaning of the film. It is, as Hitchcock prescribes, a nonsensical unimportant plot device that simply starts the ball rolling. As such, it contributes to the general confusion towards what the film is truly about and breaks any trust the audience placed with the author. Misdirection is fine if the end result is some greater meaning. Misdirection because one doesn't understand story leads to ambiguous and forgettable fare.
If left unconvinced, take note that master storyteller George Lucas described R2-D2 as:
the main driving force of the movie...what you say in the movie business is the MacGuffin...the object of everybody's search
If George Lucas relies on the MacGuffin to explain his stories, then you know it has to be a broken story concept. To be fair, he does state that the MacGuffin has more importance than Hitchcock attributed to it, but really...R2D2 the driving force of Star Wars? That would imply that once R2 is found, the story would be over. Add to this ridiculousness, the fact that the prequels were storytelling disasters and this whole fascination with the MacGuffin seems clear.
It is a tool used by those who don't fully understand why and how stories work.
Sometimes, in the case of Hitchcock, this misunderstanding has little to no effect on the final product. His films are masterpieces that, when their stories don't work, overcome this weakness with talent and panache not seen in many filmmakers.
In the case of Lucas though, it becomes clear that this concept needs to be put to rest. The MacGuffin is a joke. And in the same way we laugh at our ancestors who used to think that the Sun revolved around the Earth or that sea serpents lay in wait at the edge of the ocean, we need to have one hearty last laugh at this concept and then erase it from our collective memories.
What most people don't realize when they're talking about the MacGuffin is that the films they are referring to are actually stories with an Story Goal of Obtaining. Casblanca has it. So does Unforgiven and Reservoir Dogs. But The Sixth Sense doesn't and neither does Hamlet. These last two films have completely different Story Goals that have nothing to do with Obtaining.
This is where Authors get in trouble. When the suggestion is made to "add in a MacGuffin" they are in essence setting up an Obtaining goal (whether it be a Crystal Skull or a mysterious briefcase), when the rest of their story might not have anything to do with acquiring thematically. There are stories that have nothing to do with finding some illusive object.
Every single thing that ends up in a story, especially in a screenplay, needs to have some meaning, some connection with the Author's ultimate message. There simply isn't enough time to fart around with nonsensical concepts. Trying to force something like that into a great story will only break it, resulting in a story that ultimately, no one will care about.