Why experts are often the worst teachers

In Made to Stick, brothers Chip and Dan Heath tell the story of a 1990 Stanford experiment. Students were split into "tappers" and "listeners." Tappers picked a famous song like Happy Birthday and tapped out its rhythm on a table; listeners tried to name it. Before the reveal, tappers predicted listeners would guess right about 50% of the time. The real hit rate? 2.5% — just 3 songs out of 120.

The gap comes from what the Heaths call the Curse of Knowledge. The tapper hears the full melody in her head, so the taps feel obviously musical. The listener hears only disconnected knocks. Once you know something, you can no longer imagine not knowing it — and you assume others share the context that is actually only in your head.

This is why brilliant experts often explain things badly: they skip the very steps a beginner needs, because those steps feel too obvious to mention. The Heaths argue the cure isn't to "dumb down" ideas but to make them concrete — swap abstractions for things people can see, touch, and picture, the way a tapped rhythm needs the actual tune to make sense.