The goofy first line and the poisonous prologue are the consequence of too much focus on being interesting. But it goes without saying that an interesting (or worthwhile) start is good.

Or a book might start with no interest.

A few miles south of Soledad, the Salinas River drops in close to the hillside bank and runs deep and green. (Steinbeck, Of Mice and Men)

The reader should give you some grace on the start. First, it's the most difficult location in the book to make a scene interesting. Readers who do not give any slack will want that goofy, hyper-interesting start, which will then impair their reading experience.

Some authors impinge on that slack, in my opinion. They start with an uninteresting description of scenery, for example. But we are back to the issue of readers liking different things. And some authors are famous, they expect the reader to keep reading.

So it's good to try make the start interesting, no matter what kind of start. Scenery can be interesting. Life-as-normal can be interesting.

Getting to the Next Sentence

"Is this seat taken?" I asked the attractive young woman sitting by herself in the lounge. (The General's Daughter, DeMille, 1992)

That's mildly interesting. The reader can feel the main character's desire (for something); the reader can wonder what will happen.

That sentence is not interesting enough to sell a book or cause a reader to want to read the whole book. The author wasn't even trying for that. But it does make the reader want to read the second sentence. That's a very modest goal. But it's good enough.

Easy Reading

First, this keep-going sentence was easy to read. The words are simple, and the grammar is simple. So the reader has no reason to stop -- the reader will anticipate that the second sentence is just as easy. And there's momentum – the reader is already to the second sentence and travelling fast. It would take conscious effort to stop after that sentence.

In contrast:

Infant snow drifted down in gentle whorls . . . (Witchwood, Mafi)

I do not off-hand know what infant snow is. If I give up and skip over the first two words of this book, I am already disengaged. If I stop to think about it, I have lost momentum.

Those two words are harder to read than Crais' entire sentence.

Thinking about it . . . If the snow is coming down, it's new. It would be newborn snow. And it can be called just "snow". So that's an empty metaphor.

Whorls is a relatively uncommon word. I know it from fingerprints, where it means lines going in circles. Snow can't do that. For snow, I think "whorls" means "swirling" or "whirling". That meaning is not in every dictionary. The author could have said those more accurate words.

Do you have any gentle whorls on your fingers? Right, you too have no idea how a whorl can be gentle. Presumably the author meant the snow was coming down gently, which (1) the sentence does say, and (2) then the snow wouldn't be swirling. That sentence isn't even over; the nonsense continues:

 . . .flakes as large as pancakes glinting silver as they fell.

Are the flakes as large as pancakes? That's hard to believe. A reasonable guess is hyperbole. Um, that's a second thought. "Glinting" is not normally a verb, and "silver" is impossible for me to imagine.

And, yes, I did not stop for 5 minutes to try to figure out that sentence. I glazed over it, then I stopped and thought "I hope the next sentence is better."

Will the Next Sentence Solve the Problem?

He was an old man who fished alone in a skiff in the Gulf Stream and he had gone eighty-four days now without taking a fish. (The Old Man and the Sea, Hemingway)

What is going to happen to the old man? Is he going to take a fish? Hemingway is trying to interest the reader in the whole book. That sentence creates no interest for the next sentence – no one thinks the next sentence is going to say whether or not the man caught a fish; you have to read the whole book to get the resolution of that.

What happens to the man asking the woman about the seat? The next sentence:

She looked up from her newspaper but didn't reply.

The next sentence could have been description or a flashback, with no continuation of the scene. (Those do come, of course.) But it was not. Instead, the author created a conflict, increasing interest. Now I would say there was enough interest to finish reading the scene.

In theory, the reader could be led through the book sentence by sentence. In practice, it won't work that way. First, there will be boring sentences. Ideally, the author will eliminate those in editing, but mistakes happen and no one is perfect. Second, the author will build multiple reasons for the reader to want to keep reading.

The next two sentences of that book were uninteresting, but not a turn-off. Then a few short senteces of mildly interesting conflict led me to the eighth sentence, which I really liked.

I sat opposite her at the cocktail table and put down my beer. She went back to her paper and sipped on her drink, a bourbon and Coke. I inquired, "Come here often?"
"Go away."
"What's your sign."
"No trespassing."

I was determined to read more.

Another Example

It is my first morning of high school. (Speak, Anderson)

That doesn't generate any interest, as far as I can see. It doesn't impress. First morning of a new year of school is a well-worn trope. I can't find any incentive to keep reading.

But there's also no reason to stop. It's nine simple words. Nothing is objectionable. The next sentence:

I have seven new notebooks, a skirt I hate, and a stomachache.

That generates interest –why does she have a stomach ache? Probably no one is going to be impressed by it except me, but it's a brilliantly written sentence.

Action Starts

Action starts tend to create interest for the next sentence; The scene is starting. To find out what happens, read the next sentence.

Descrption tends not to create issues, and anyway they tend not to be resolved with more description or by the first sentence of action. The goofy first line is more likely to create a topic.

More Generally

In the first line, the author is perhaps trying to create interest. Most authors do. The author doesn't think about what that interest extends to. At one extreme, it might be just the next sentence; at the other extreme, it might be the whole book )or up to the conclusion).

In the middle, it might be the scene. One example:

Andie Miller sat in the reception room of her ex-hanbad's law office, holding on to ten years of uncashed alimony checks and a lot of undresolved rage. (Maybe This Time, Cruise)

Why is she angry? Why does she have uncashed alimony checks? What's going to happen when they meet? The next sentence doesn't resolve anything, but the scene does.