Where to start a story? It is a problem that all authors grapple with? Do you start with the inciting incident or do you start with the ordinary world that is about to change?
For a romance -- the inciting incident is the MEET. This is the thing that starts the spine of the story -- namely the growth of the emotional relationship between the hero and heroine. Without them meeting and interacting, the relationship can't change and grow. And the MEET doesn't mean necessarily the first time in their life that the main protagonists meet but rather that encoutner that changes their life.
Everything that happens before is called the set up or sometimes the bridging conflict. Bridging conflict is also a subplot. It is what needs to happen BEFORE the meet so the author doesn't spend time explaining. It helps with dealing with certain aspects of back story as the author can SHOW and not TELL. (Back story, unless done as a flashback, is invariably telling or narrative. The reason for using the term bridging conflict is that it provides the bridge into the story for the reader.
In series romance, there is not much of it. For one very practical reason -- the author doesn't have many words and the focus must be on the main spine of the story. So the meet or some portion of the meet should definitely take place within the first chapter. With single title, the author has more time. I should point out that historicals with their longer length do have a place for subplots but that those subplots MUST influence the main story and ultimately directly influence the relationship.
One way of determining where to start is to start with the MEET. Does it make sense? Is the reader immediately drawn into the characters' predicament. Why or why not? Why are they in conflict? Why is it a confrontation? Is it immediately understandable or will the author have to provide table dusting backstory/explanation?
If it doesn't make sense, what needs to happen before the actual MEET? Are there any opportunities for good narrative action that you have missed? Can you open with a bang?
You have precisely 6 seconds or thereabouts to hook the reader.
How are you going to create questions? How are you going to have one character literally or figuratively fighting for their lives? Or fighting for something that they passionately believe in? What is the POV's character's stakes and why is the reader going to immediately care about the character? How can you build the anticipation of the first meet? Have you let a great opportunity for narrative action that will draw the reader into the story go to waste if you start with the meet? Why is she going to turn the page? Why won't she be able to put that book down?
For example, when Kate Allan and I wrote The Lady Soldier, we had to add an entire new first chapter. Originally the book started with the heroine Jem having made it through the battle meeting the hero after she had been promoted from the ranks. John Hale pointed out that the battle actually represented a chance for great narrative action as it SHOWED her bravery and her fighting for her life. Never let the opportunity for good narrative action go to waste he advised. That motto has been engraved on my mind ever since.
Another case in point are my Viking books. None start with the hero or heroine meeting. Instead they all start with a battle. The meet takes place in the aftermath of the battle. During the battle, either the hero or heroine or both lives are put in danger and it is this danger which hopefully will have the reader turning the pages until the couple meet and are forced into close proximity with each other.
Compromising Miss Milton starts with the hero being attacked. Originally I started with the heroine finding his body but decided that it was far better to start with action. Towards the end of chapter one, the heroine fishes him out of the water and saves his life.
An example from a recent contemporary is Kat's Pride by Sharon Kenderick (Kat and Dare Devil Spaniard in the US). The first chapter is devoted to Kat arriving on board Carlos Guerrero's luxury yacht and it slowly dawning on her that she is there as a hired help, rather than as an honoured guest and what is worse that her new *employer* is the man she most wants to avoid in the world. The couple meets in the last two paragraphs of chapter one.
With the short story I'm writing, the setup has to be almost non existent and the romance does have to start immediately. 10k is not very long. The same is true for an Undone.
In conclusion, think about how you are going to provide a compelling bridge for the reader to cross into the story's world. What must happen? What does the reader need to know? It is harder than you might think. Figuring out where the Meet happens and why is a good place to start.