A man is told on the phone that his girlfriend is in danger from the criminal types he used to hang out with. He rushes out of the house and notices how beautiful the flowers in the garden are.
This is going to slow the pace, but NOT because it is slowing down his journey to the car, which will get him to his girl etc.
Consider: The same man rushes out of his house to rescue his girlfriend, but he is intercepted by his parole officer who is there to check he isn’t consorting with nefarious types, otherwise it’s back to the slammer ... What does he do now? (Can parole officers do that? I don’t know, I’m making this up).
Even though I am slowing down the character’s progress, I am not slowing the narrative. Because pace isn’t about how long it takes to get to the next thing, it’s how long it takes to get to the next interesting thing.
If the thing that delays him is believable and problematic, it won’t slow the pace of the story. What slows pace, as in the example with the flowers, is stuff that’s pointless. Or boring. Or unbelievable. Even having the parole officer (or whoever) turning up requires handling in a way that feels real to the reader, because if the reader has to stop to work things out or convince themselves it sort of makes sense, that will kill any momentum you’ve built up.
The way to tell if something is working or not is to remove it from the story and see if the story still makes sense. If it does still make sense, that does NOT mean it should stay removed. The writer may have a wicked line about the yellowness of daffodils that it would be a crime to deprive the world of. What you need to do is rewrite it so the non-essential scene becomes essential.
If the man rushes out of the house and is brought up short by the sight of every flower in the garden ripped out of the ground and the petals (the yellow, yellow petals) spell out the word ‘Bastard’ then that is not going to slow the pace. That is going to add to the pace, because you just got to interesting even sooner than the reader was expecting.
The reader thought, right, he’s going to get in his car, go to the warehouse, fight the bad guys ... but the moment he walks out the door, bam! — parole officer, weird flower message, whatever. It may not seem like a very bam! moment out of context, but within a story that’s all it takes.
You can up the pace by editing out superfluous stuff, but you can also up the pace by adding things that are creative and inventive and unexpected (although avoid ridiculous), making the narrative less predictable. It doesn’t have to be large scale action set pieces with imminent death and destruction.
A 40 year old guy looks out of his window at the tree in the garden he planted with his dad, whose funeral he just attended ...
I know I want to reference his dead dad through the tree. Him staring out of the window, no matter how emotional for him, is dull to watch. Forget the concept of grief and the journey of life implicit in the act of remembrance, look at it objectively. He’s a man looking out of a fucking window. How can I make it more interesting?
Let’s say I have him walk out to the tree and attempt to climb it the way he did when he was a kid. That slight shift in perspective is enough to up the pace. The reader wasn’t expecting him to do that in his nice suit and tie. Unexpected equals interesting equals pace. Finding that in a scene isn’t hard, but you have to be looking for it.
Interesting can mean a million things. It doesn’t necessarily have to do with the main plot. Or with life and death situations. Or running around like a maniac.
A man can be driven to the airport in a taxi at great speed, but that doesn't make it an interesting scene. If the scenery whizzes by, he sits quietly in the back, and he gets to the airport on time, what makes the scene feel slow is that it's boring. Boredom slows down everything.
What is the purpose of the taxi ride? How can you show that in an unexpected way? If you can't think of a way to do that, then cut it. And if you can't think of the purpose of the taxi ride, other than people sometimes take taxis to get to places, then definitely cut it and start again.
1. Pace is how quickly you get to something interesting.
2. You get to define what interesting means, but be honest with yourself.
3. It is always possible to get the same message across in a more inventive way. Harder, but definitely possible.
Post script... Sometimes scenes are intentionally boring, to provide contrast and set tone and what-have-you, but it’s perfectly possible to convey boredom in an interesting fashion, a subject I tackled in my post Boring Characters