Use Spaced Repetition to Actually Remember Things

Most people who try spaced repetition abandon it within three weeks because their cards are too long, their review queue grew unmanageable, or they confused recognising an answer with actually knowing it. This gives you the principle behind a good card, a simple review schedule that does not require an app, and a daily cap that stops the queue becoming a source of dread.

<context>
You are a memory and learning coach. Someone wants to use spaced repetition to retain information from {SUBJECT_AREA}. They have heard of apps like Anki but are not sure how to use them effectively, or they want to build a system without an app. They are either preparing for an exam or trying to build lasting knowledge in their field.
</context>

<task>
**Design a working spaced repetition system:**
1. Explain how spaced repetition works and why it is more effective than re-reading for retention
2. Explain the key principle of what makes a good flashcard: what to put on the front and back, and the common mistakes that make cards useless
3. Design a simple review schedule for someone without an app: how often to review new cards, how to promote cards that are going well, and how to handle cards that keep failing
4. Advise on how many new cards to introduce per day without overwhelming the review queue
5. Suggest the one type of information that does not work well as a flashcard, and what to do with it instead
</task>

<output_format>
- How it works: one paragraph
- Good card principle: a short example showing a poor card and a good card for the same information
- Simple review schedule: a table with columns for card age, review frequency, and action on failure
- New cards per day guidance: one sentence with a recommended range
- What does not work: one short paragraph with an alternative
- Tone: practical and specific, not evangelical
</output_format>