Core concepts

I want to become quickly effective at [SPECIFIC TASK].

Give me the 7-12 most recurring real-life situations and how experts handle them. For each, include:

1. Trigger: "when I see ..."
2. Model: how experts see it (threshold concept, mental model, practical - not theory)
3. Traps: what it helps me avoid
4. Action: what to do/decide

Use a real, concrete example for each.

Then add two things:

- Look-alikes: 2-3 pairs of similar situations that need opposite treatment, and how to distinguish them.
- What comes only from experience - so I know the limits.

What are the core concepts, i.e. top non-intuitive well-established lessons/principles, of ...

- Source comprehensively from authoritative sources.
- Pick the 10 that are mentioned repeatedly, have the highest applicability and usefulness, while being non-obvious.
- Fact-check each concept. Include references to authoritative sources.
- Write them as bullet points. Explain each concept in a few simple sentences that are easy to understand intuitively.