The Seven Limitations of Expertise

Experts don't make good teachers for the following scientifically based reasons.

1. Domain Limited - Experts are limited to their domain and that expertise does not extend to other domains.
2. Overly Confident - Experts over estimate their abilities when it comes to their field of expertise.
3. Glossing Over - Experts gloss over information that they believe is irrelevant; therefore, missing details that may be necessary to solve a problem.
   
4. Context Dependent - Without contextual clues, experts are not that accurate.
5. Inaccurate Prediction, Judgement and Advice - Experts fail to predict how quickly novices will learn something.
6. Bias - Experts are biased toward their domain
7. Inflexible - Experts can adapt but often prove inflexible when changes are deeply rooted.

Source: Cambridge Handbook of Expertise and Expert Performance (PDF of Chapter)