Crystal says the dynamic nature of the Internet makes it difficult for comprehensive analysis of its effects to stay up-to-date.

VOA: standard.2010.01.16

The security analysis is difficult to do right.

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Sometimes the binary nature of external analysis makes it difficult for outsiders to hold both realities in their head at the same time.

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Typically, when a retracement is ending, it will be a difficult time for the investor or trader as the market momentum and the sentiment is at a level that causes many to question their analysis making it more difficult to act.

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