One of the most valuable qualities anyone can have is speaking concisely. You don't just communicate more efficiently; you also manage to add more content into the conversation. More content: more gets discussed: more gets done.
Whenever we demo our product, we try to be as concise as possible, especially in the first few sentences when describing our product.
That said, articulating your vision has definitely worked well for us when approaching Berkeley and Stanford students. It helps them with the bigger picture of where we're going and what we're trying to accomplish. But when it comes down to functionality concepts, it's better to be concise.
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