Incident or conflict is the cornerstone of any novel. Without it, you have 60,000 words of gibberish with no direction or purpose and most likely, no audience. Every novel must contain one incident that flows throughout until the resolution.
For a mystery, this is the overall who did what and why. For romance, it is the beginning of a love story. And so forth. This is what drives the story to its conclusion.
It should be introduced to the story at the earliest possible point. If it isn’t, not only is there a lot of chopping that will need to be done during revision, but there is the question of keeping the readers interested long enough to get to that point.
Does this mean it has to be introduced immediately on the first page? No. But you also can’t have six chapters without it.
For example, when I wrote Tortured Dreams, I eluded to the incident in the prologue. However, there had to be some character development done before the story could continue. So while I gave an idea that something dreadful had happened in the prologue, the incident isn’t explained until chapter 4.
The trick to this was the background being given about the main character. Aislinn Cain has survived two serial killers. She goes into some detail about the serial killers. She tells of her formal training as a Medievalist. She tells of her most recent encounter, which she is still recovering from… And she mentions there are two “feds” in her apartment, but she isn’t entirely sure why.
From this, it is logical for the reader to conclude that the “feds” are there to talk to her about a serial killer and that her formal training as a Medievalist is going to come into play. Without that, I would not have been able to delay the “full encounter with the feds” until Chapter 4. It would have had to be spelled out much earlier.
The prologue is the perfect place to incite the initial incident. It and the epilogue are the two spots where the writer can step away from their developed characters and through in something totally different. It doesn’t matter if the story is told from first person or third. The writer is able to step outside the bounds of whatever they are constructing. This makes the prologue ideal for inciting incident without introducing characters.
In the sequel, Elysium Dreams, the prologue has nothing to do with Aislinn Cain. It has everything to do with the killer. It is HIS moment. HIS plan is being put into action. The same is true of Dark Corners. The prologue contains no character introduction or development except the finding of an anonymous dead body and the woman that finds it.
The initial incident should help set the tone for your book. If your inciting is comical, the book should carry some humor. If the initial incident is dark and mysterious, then those overtones are expected to continue. Keep this in mind when creating the initial incident. You don’t want to start your book with a bar fight if violence and group hysteria is not going to figure prominently as a theme in your book.