What do people usually get wrong about this?

Before you teach something, or before you assume your own version is right.

List the common misconceptions about the topic below.

For each, give me:
- The wrong belief, stated the way someone would actually say it
- Why it is appealing: what makes it feel right
- Where it comes from: a bad analogy, an oversimplified explanation, a case where it happens to be true
- What is actually true
- A concrete case where believing the wrong version produces a wrong outcome

Order by how widespread they are. Include at least one that people who are moderately experienced in this area still hold, not just beginners.

Topic:

Scrutinising ideas. Where a concept stops working, what people get wrong, and whether a claim holds up.