Sometimes I think this avoidance-of-narrative-introspection is a "guy writer" thing. Something that E. Hemingway started--and I blame him for a lot of stuff. For the stripped-down writing style that has been so popular, for one thing. And for the "girl-cooties" school of thought about "litrachure." It's not that I am fond of purple prose, but it does sometimes seem that all metaphors and adjectives are now considered suspect in certain circles. Ah well.
I tend to blame television and movies for the lack of internal reaction in novels today, not the "show vs. tell" issue. If we're in deep POV, the thoughts and emotions are showing, though they can seem like telling, I suppose. These days, a lot of newbie authors, the ones I judge in contests, tend not to go on and on with backstory and what the characters are thinking-- they've been trained out of that, I suppose. Lately, I've seen the pendulum swing too far the other way. They write prose that reads a lot like a screenplay, with dialog, action, and nothing else. Which means a lot of the characters' motivations for their actions are completely missing.
If we don't get what the character thinks about something, or how they feel about something-- about who a person is, or what that person does, or about what they themselves do--then we don't get to know who this character is, and we don't know why they do what they do, and without knowing the character and understanding them, we don't care what happens to them. We have to explain what's going on inside a character's head. It doesn't take a whole lot. Just...enough.
Here's an excerpt from the first of my Rose books, The Compass Rose, to demonstrate what I mean. (I'll put the internal reaction in another color to make it easier to spot):
Torchay had changed out of his finery into old trousers, his tunic off against the heat as he worked through his bodyguard exercises.
“Don’t you usually do that earlier in the day?” Kallista tossed her pendant on the table beside the big bed and kicked off her shoes.
“I did.” He finished the flowing form he was doing and stopped. The faint sheen of sweat over his lean musculature tempted her eyes to look, to drink their fill. “I felt like doing it again. I didn’t expect to see you before dawn.”
“Yes, well...” She tugged her fingers free of the thin snug leather and pulled her gloves off, flexing her sweaty hands in the slightly cooler air. “Didn’t work out.”
Torchay walked toward the table. Kallista backed off. She couldn’t bear being so close to him. Not now. He poured water from the pitcher into a cup and drank it, then poured the rest into the basin and splashed it on his face. Kallista watched his every move.
When he had dried his face with the flimsy towel, he turned and saw Kallista watching. “Can I ask you somethi—? No.” He shook his head. “Never mind.” He hung the towel up and reached for his hair to release his queue.
“What?” Kallista loosened the laces of her dress tunic. “If you have a question, ask it. You know you can ask me anything.”
She looked up and saw his gaze focused on her. The candlelight reflecting from his eyes made them glow with blue flame. She lost herself in them for a moment before she recalled he’d asked her a question. “Yes, of course. Anything.”
Once more he hesitated, seeming to look for something as he gazed at her, but what, Kallista didn’t know. [I put all this in a different color, because part of it is what K. thinks he's doing.]
“All right,” he said finally. “I will.” He ran his fingers through his unbound hair and it fell in waves around his face, crimson in the candlelight. “When you have gone out hunting all these years—“ He paused for a deep breath, looking away only an instant. “When you have hunted a man, why did you never choose me?”
Kallista swayed, Torchay’s question touching unseen things deep inside her, drawing her tight, opening her up. Her nipples beaded beneath the brocade weave of her dress and she tucked her hands beneath her arms, more as a guard against unwanted magic than an attempt to hide her body’s reaction. [all of the previous is a physical reaction--with a teensy bit of explanation, but after is where we get the true emotional reaction.] Why did he have to ask her that question now? Now when she wanted him so much it made her mouth dry and other places all too wet?
“I— It’s not that—“ Goddess, what could she say that wouldn’t either insult him or encourage him?
Torchay waited, his face an impassive mask, candlelight licking over his sculpted form, tempting her to do the same. She curled her hands into fists against the urge to touch.
See? Most of it is action and dialogue. But the internal reaction is sprinkled in with it, and that's all you need. Not a whole lot, but enough to expand on what is physically happening. You need both. The action and dialog AND the internal reaction--mental and emotional--to the action.
When I judge contests, I often feel like a psychoanalyst for the characters, given all the times I'm writing "Why?" or "And what does he feel about that?" Those things do need to be included. Not over pages and pages, but all the way through every bit of it.