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  • Aaron Wolfson thinks this is interesting:

You will notice that these are large enough groups to be markets but are specific enough to have some very similar behavior patterns. That’s important. Remember, this is a market to which you want to sell your product. If you want to sell a lot of your product, it makes sense to pick a market that has enough people to eventually support your growing business. The specific part is important because you want to be able to easily identify those people for your research.


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Essentially, "why should this thing exist?"