Writers want to create the perfect story that suck their readers in. However, there are some potential traps that can get in the way of that.
For readers, there's nothing worse than finding a romance that has all the right elements -- great characters, terrific plot, great setting -- and then finding yourself stumbling along when you try to navigate the prose.
Here's an example from one of my early novels: "Curious, Carson sat down, wishing instantly for a softer chair such as the kind he enjoyed much more."
As Yoda would say, "Sucks it does." That sentence both makes readers stumble on its awkwardness and makes them fall asleep. If I were writing that sentence today, I would probably change it to simply "Carson sat down, curious." Most likely, the chair isn't important, so I shouldn't have spent so much time on it. Instead, the sentence meandered along, like so many other sentences in that period of my writing. You'd think I was getting paid by the word.
Making a reader laugh when you didn't want her to is bad, too. A reviewer I know recently found this gem in a recently published romantic suspense novel -- "Her blood turned to liquid." Something tells me the suspenseful moment was ruined for that reviewer as she was rolling on the floor laughing.
Other style elements that might trip up readers include: annoying dialogue tags; hard-to-follow headhopping; and hard-to-read dialect. As with any writing technique, a little means a lot. Using dialogue tags other than "said" now and then can be fine, but using them on every page is distracting. Many writers can headhop without distracting the reader; that's fine. A few writers can create dialect that works and doesn't get in the way, but most can't.
Purple prose is a close cousin to bad style. Generally, purple prose is thought of as overly florid writing in love scenes, particularly writing that's chock-full of euphemisms for body parts. Some readers also use this expression to refer to overdone writing in the book as a whole, but it's most commonly used to refer to the sort of writing found in overblown love scenes.
If you don't like to use words like "penis," let alone slang words for body parts, then you can still write a love scene. And if you like writing florid prose, that's fine. But avoid going over the top. keep in mind that there's no need to use terms like "her hidden garden" and "his love juices." One reader actually came across a time travel romance that referred to the heroine's "chalice of flesh." The fact that she remembered the passage so clearly is not a good sign. It means she was so distracted by it that she still remembered it long enough to share it with other readers, no doubt shaking her head in disbelief the whole time.
You can talk about sex without using what some romance readers refer to as silly sex (for more, see http://www.likesbooks.com/sillysex.html. If you don't want to talk about body parts, then don't. It's better to avoid speaking of body parts than use euphemisms that pull the reader out of the story.
And if you do write about body parts, then you owe it to your readers to get it right. I once came across a love scene in a Western historical romance that referred to "the pebble of flesh at her entrance." My first thought was "Oh my God, it moved!" My second thought was to get that author a copy of a basic anatomy text. I wasn't just yanked out of the story at that point, I was wrenched from it.
The article on Research Flaws in Romance Novels covered historical and research flaws in general. You don't have to follow all the advice in that article. However, even if you're writing a "wallpaper historical" (a historical romance where the setting is relegated to the background), you should avoid really big errors. I define "really big errors" as those that are big enough to catch the attention of a reader like me, who wouldn't know a duke from the Duke of Early and doesn't worry too much about historical accuracy. If I notice your error, then it was a big one, and it was probably big enough to bug a lot of other readers.
Big errors include things like Welsh castles with steel gates in the year 1000; people using zippers in Regency England; tomatoes and potatoes showing up in Medieval England; and perhaps the silliest error I have heard of, a Regency era heroine traveling to Paris (even though France and England were at war when that book took place) and seeing the Eiffel Tower, many decades before it was built. Even people who write books taking place in the U.S. aren't free of errors -- some writers have set their stories in cities and states that hadn't been founded yet at the time the book took place. (Remember, if you're writing a book set in the U.S., readers are even more likely to find your mistakes as most of your readers live there.) An error of that magnitude is guaranteed to make even the most laid-back and forgiving of readers throw your book down in disgust.
Do both yourself and your readers a favor. Never assume anything about history. Before you put something in your story, especially if it's a large, metallic object, look it up to make sure it existed at that time.
Infodumps are the opposite of bad history. This is a term term science fiction readers came up with to describe passages where the author goes on and on (and on) about background -- but infodumps can be found in all types of books. Even if your grasp of history or setting is good, you should avoid pouring the details over the story like butterscotch. Avoid the temptation to have your characters tell each other about history or facts -- especially if they are talking about something they both already know. The more your characters blather on, the more you risk losing your readers.
The worst type of infodump is when characters lecture each other about facts they already know. This sort of dialogue is known as "As You Know" dialogue because in its most obvious forms, the characters say things like "As you know, Jane, the Inner Harbor houses the National Aquarium." This is jarring not only because it is infodump but because nobody talks like this in real life.
On the other hand, if you can integrate the background information smoothly into the story, your readers will be grateful. Those readers who don't want a lot of history or details will still enjoy your story because they can read it and learn stuff without being distracted by the facts, but you will still win over readers who love reading stories with lots of details.
There are two types of jarring names -- bizarre or silly names and names that don't belong in a particular era. Sometimes, it's necessary to give the characters strange names. (Many readers loved Judith Ivory's Black Silk, in which the heroine was named Submit.) But often, those names will just come across as affectations. How many times can you come across a hero named Roque without wondering if the author is making a naughty joke? Especially if Roque is in love with a heroine named Honor? Readers have come across that sort of thing before, so they won't be impressed by your imagination. They will be grateful if, for once, someone writes a romance novel about an Ellen or a Susan instead of a Devona or Caressa.
Also, is the name easy to pronounce? If you're writing a romance set in, let's say, Wales or Ireland, you'll probably want to include some of the lovely names native to those regions. However, readers won't be able to pronounce many of those names from the spelling given. In those cases, it's a good idea to include some kind of pronunciation guide.
Finally, remember to use names that are accurate to the era you're writing about -- while still avoiding accurate names such as Egbert that will make modern readers laugh. Many names weren't even in use until recent times. While Whitney, My Love is a best-selling historical novel set in Victorian times, many readers refuse to read it because the heroine, Whitney, has such a modern name.
Do you remember that scene in Pretty Woman where the heroine starts eating a croissant, and moments later, she is eating a pancake? This is what is called a "film flub," and it's one of the most famous continuity errors in modern-day moves. This type of error turns up in novels as well.
All too often, characters change eye color and hair color from page to page. Other errors can occur, too. And readers will notice, even if you and your editor did not. There is a Western historical romance in which the hero rides into town on a spirited black steed, and mere pages later, his horse has become a gray gelding. This occurred in the first chapter. No doubt, many readers picked up that novel, started reading it, and then shouted, "Whoah boy!"
Many writers keep timelines of the events in their novels and charts of the physical characteristics of their characters so that they can avoid these errors. It's worth the extra trouble. After all, you don't want to pour your heart and soul into a novel, only to get letters from readers complaining because your hero's eyes were gray in Chapter Six, blue in Chapter Eight, and green in Chapter Nine.
Even if you're writing contemporary romances, you can still end up with anachronisms. Always keep track of the age of your character and try to fit their likes and dislikes to their age. If you're heroine is 23, it's unlikely she likes PT Cruisers and listens to Falco. It's more likely that she drives a VW Beetle and listens to Sheryl Crow. In other words, don't give her your likes, give the poor woman her own likes. Letting a 20-something heroine listen to 1970s or 1980s rock without giving an explanation for her likes is the equivalent making her wear parachute pants. This isn't to say your 20-something heroine can't listen to Falco (or for that matter, to Bob Dylan), but readers will be more likely to accept this if it fits her personality. Then it won't seem like an anachronism at all.
Your characters' slang should match their age groups as well. Your 20-something heroine probably doesn't go to the "record store." They don't remember records. They will call it a "music store" instead. This isn't really a big deal, but it can bug readers, especially if it happens several times in a story. If it happens often enough, readers will begin to doubt that your character is really 20-something; instead, they will begin to suspect that she is a 30-something heroine with a different age tacked on.
The "Ick Factor" is something gross that can pull a reader right out of a scene. It's usually found in love scenes, but for some readers, the Ick Factor can be something more abstract, such as a heroine falling in love with her stepbrother or a romance with a big age difference. The abstract Ick Factor is hard to avoid -- and you shouldn't worry about trying to avoid it because it's impossible to write something that doesn't offend someone.
Most commonly, however, readers use "Ick Factor" to refer to something that is physically gross -- and sometimes funny as well. Such as the scene where the hero told the heroine to lick caramel sauce from her breasts. Most readers who learned about this scene weren't sure if they should laugh or gag. Sometimes the Ick Factor is just ... icky. For example, years ago, I started reading a "glitz" novel where the heroine's cousin took the heroine's virginity with a soda bottle. Later, the heroine walked in on her cousin having consensual sexual relations with an older male relative. I didn't make it much farther in that novel. Maybe there was a reason for all these things to happen, but I didn't feel like waiting to find out. It wasn't just that the details were gross, it was that they seemed "tacked on," added to shock the reader. Compare that with the infamous Flowers in the Attic. Yes, the brother and sister finally slept with each other, but that came only after they were forced to live in close quarters, cut off from the rest of the world, for years. It was shocking, but it was also inevitable.
In romance, a great example of a controversial and shocking scene is the scene in Robin Schone's The Lover involving worms and a coffin. Yes, many readers loathed this scene, as well as the parts about the hero's horrible childhood. But a lot of readers had no problem with the worms scene, understanding what it meant to the characters -- in particular, they way it connected to the hero's terrible childhood. What's important to remember here is that the worms had a significance to the characters. This detail wasn't just thrown in to shock readers.
You can still put this sort of detail in your stories. In fact, like Robin Schone, you might not feel right unless you put lots of gritty details into your book. Sex is "down and dirty." But if you do put these details in your story, make sure you have a real reason, other than just putting in something shocking. On the other hand, as far as I could tell, there was no discernible reason for the soda bottle scene in that glitz novel.
Unless you can really pull it off, avoid having your characters think over things over and over and over again. When I read some books, I'm surprised the characters don't walk into walls -- they're so busy ruminating over every little thing that happened to them during the course of the story that they probably can't see what's going on in front of their eyes.
Interior monologue can be vitally important to stories. It's one of the techniques that sets novels apart from visual works. However, avoid repetitious repetitious repetitious (you get the picture) interior monologue. If the hero worries about his feelings for the heroine once or twice, readers will get the picture. But if he keeps worrying about his feelings, going back over old ground repeatedly, then readers are likely to get fed up and throw the book down.
As with any other writing rules, these rules were made to be broken. If you can break these rules and still keep the attention of your reader, more power to you. If you can break several of them at once and still keep the reader's attention, I want a copy of your book!