This is an issue that was indirectly brought to us at least once a week by your various emails over the last few months. If one were to look at most of the plot hole pages on this website; the easy conclusion would be to assume that action and science fiction movies have the most ridiculous screenplays compared to other film genres. After all, they are the ones with the longest lists.
This is a misconception that needs to be addressed. The amount of plot holes a movie has is simply a unit without a measurement. If a science fiction movie has 6 plot holes but a comedy only has 3; it does not mean that the latter has a better constructed script. The unit of measurement that needs to be attached to the number of plot holes is the risk factor. A movie that takes on higher risks will inevitably be prone to more plot holes. And thus, its higher plot hole counts can be excused.
There are 4 risk factors a screenwriter will have to choose that will inevitably affect the risks of plot holes in his/her story:
When you write a screenplay and you decide upon what type of story it will be – those 4 elements will inevitably come up in your calculations no matter if you are conscious of them or not.
The first step is the tone. Do you want to make a serious movie (drama, epic historical, etc) ? Or do you want to make a funny movie (rom. Com, musical, etc) ?
If you make a funny movie – it is by definition less likely to have plot holes (with all other measures being equal). Because in a funny movie, the premise is understood that many, if not most, of the characters will be stupid. Everyone can do dumb things because they are dumb and if they happen to do something smart; then it’s an accident and there is no contradiction.
But if you do a serious movie, the audience will expect the characters to behave like normal people which make character contradictions less acceptable than an imaginary character in a funny parallel universe. (Still acceptable in some contexts, but less).
The second step is the scale of the conflict. Do you want to make a story about a man who lost his golden tooth and goes on an adventure at Wall-Mart to find it (personal scale)? Or do you want to write a story about a general who witnesses an international conspiracy to assassinate a foreign president (global scale)?
In the first scenario, plot holes are less likely because only a few people will be affected by the story: the man who lost his tooth, maybe his family, and a few vendors. But in the other scenario, even if most of the script focuses on the General, we have to assume hundreds of characters are involved: diplomats, soldiers, politicians, etc. And the script has to realistically interpret how all of these actors will play with each other to give a logical flow to the overall narrative.
Lastly, there is the source of the mythology. If you make a disaster movie about ghosts invading the Earth, you can pretty much do what you want because there are no known rules about supernatural phenomenon – and thus no problems of contradictions. However, if your movie is about a giant volcano that surprisingly erupts in Washington, you’ll have a harder time to make the disaster consistent and logical all the way to the end: science majors will take great pleasure in over-analyzing your movie.
With those four elements explained, the point here that is important to understand is that the number of plot holes can only be compared to similar movies of the same type. Some film genres are a lot less risky to feature plot holes, while others are almost begging for them.
For example, the movie Before Sunset has no plot holes. Even though the movie has a serious tone, the conflict is personal, there are no complex devices and scientific concepts, and the plot is simply 2 people walking and talking for 2 hours in real time. Yes the screenplay is also very good, but the premise of the movie itself protects it very well from potential plot holes.
When you take a movie like Looper, where a young man of a global killing agency refuses to kill his future self who has a vendetta against the future killer of his wife, then it will be a lot harder to make your movie plot hole-free.
If we use the tables, it would be something like this:
Science fiction movies in general, are the ones that are the most prone to plot holes; their plots are complex, with global repercussions, usually lasts for long periods of time and have to include imaginary concepts based on science in their premises. You can’t compare oranges and apples – but we encourage you to compare the shit out of the same fruits.