But I’ve seen too many people confuse detailed data with truth. You don’t know if a market opportunity exists until a real customer thinks enough of your idea to part with their scarce money or time to get it. And you don’t really know until that customer finds your idea valuable enough that they keep using it, recommend it to their friends, and purchase it again.
from Scott Anthony’s recent HBR blog post on how Innovators should use data.  
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