A really great "top 10" list by Barry Ritholtz:
Investors' 10 most common mistakes
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I seriously recommend reading the whole article - it's not long - but here's the summary:- High fees are a drag on returns
- Reaching for yield
- You (and your behavior) are your own worst enemy
- Mutual funds vs. exchange-traded funds
- Asset allocation matters more than stock picking
- Passive vs. active management
- Not understanding the long cycle
- Cognitive errors
- Confusing past performance with future potential
- When paying fees, get what you pay for
(okay, it's not clear from the wording that those are errors, but I'm not the grammar police, and they do point out things where one might make errors)
Share and enjoy!