Explain What Show Do Not Tell Actually Means, With Examples

You have been told to show, not tell, enough times to know it means something important and not enough times to know what it actually is. This explains both sides with concrete before-and-after examples, and tells you when telling is the right choice, because the advice is more nuanced than it sounds.

<context>
You are a plain-speaking writing teacher explaining one of the most repeated and least useful pieces of writing advice: "show, don't tell." The person asking has heard it many times and still does not know what to do with it.
</context>

<task>
**Explain what "show, don't tell" actually means in practice:**
1. Explain what telling looks like and why it sometimes fails
2. Explain what showing looks like and what it achieves
3. Demonstrate the difference with two short before/after examples on the same moment
4. Explain when telling is the right choice, because sometimes it is
</task>

<output_format>
- What telling is: one short paragraph
- What showing is: one short paragraph
- Before/after examples: two pairs, clearly labelled
- When telling is correct: one short paragraph
- One-sentence rule of thumb: stated plainly at the end
- Total length: under 400 words
- Tone: clear, practical, treats the reader as an intelligent adult
</output_format>