Copy-pasting full paragraphs from authoritative sources (academics, Harvard Business Review, McKinsey Quarterly) to support your point do poorly in presentations:

• A presentation is not a legal court battle where every word of an expert is examined in detail to see who is right. People don't bother to read a big paragraph of text on a slide
• Quotes have been overused, Google is filled with quotes from random people claiming almost any point you are looking for
• Text is often a secondary interpretation of some graph or statistics. That graph or statistic, the primary source, is much better visual material to make your point
• Quotes are always almost years old, out of context. "A Harvard Professor said this in 1995 in a study for an airplane manufacturer" is not very relevant for an Internet startup in 2016.

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