"Like the winding stream, writers need to know where to take the reader, down the consistent path." ~joni
Consistency is another attribute necessary to pulling off a story. We need to be consistent throughout our work so the reader doesn’t get confused. This isn’t the same as staying focused (although that helps a lot.) Consistency is where fact meets fact.
Say you’re writing a period piece of the roaring twenties. You will need to make sure that your scenes fit that era, and don’t accidentally toss in that, "She sat tapping on the keyboard all day." It is things like this that will have your reader doing a double take and say, "I thought this was 1925?"
You should never have cause to make your reader double back searching for birthdays and ages, and times of day. With consistency they will already know the time of the day that she had her first kiss, or the time his dad bought the young boy his first car.
These things might seem minor to you, but to your reader it is giving them a solid foundation of your character to hold onto. Flashbacks help a story, but if you miss the consistency check, you are certainly in trouble.
You need to be consistent in your language, consistent in terms, consistent in style. You can’t write short and to the point one-minute then lapse into a prose style the next. You can’t shift tenses or points of view; instead you need to be consistent throughout the piece.
Now long time published authors, I have witnessed, play with the tenses just to fool you, but they are masters at their trade. It is wise if you are new to the publishing world to write consistently so that your followers know your style, follow it compulsively, and look forward to the next installation of your work.
People have a tendency to like the ordinary and expecting you to write one way in one book and the same in the next and the next. They will become your followers and the ones that will promote you to "The most published author’s" list. Sure they expect the unexpected to happen in your spiritual novel or horror story, but they’ve come to love your consistent writing. That is what is going to carry you from one novel to the next.
When you read Stephen King and Dean Koontz, you know their style (although both are different, they are both extremely good at what they do.) They know what you want as writers. They feed off of knowing you, the reader, better than you know yourselves sometimes. They give you a tiny taste of what you can expect in the very first chapter and what happens, you pig out on the entire meal, over-indulge yourself into some hefty reading and wind up reading the whole book! (This is true of all novelists also, although I am a die hard King and Koontz fan.)
Know the reader; give them what they crave. Remember it is consistency that put the above authors where they are today. Without consistency they would have been shelved (pun intended) years ago.