Whatever the profile, recruit 10 people who match it.

Remember, if you’re completely incapable of recruiting those 10 people, you’ll have a hard time finding thousands or even millions of them to be your actual users. Your persona should reflect people you can find in the wild, since you’ll need to do that in order to acquire them as users of your product. If they’re impossible to find for research, either that person doesn’t exist or they exist but you’re not the right person to try to build something for them.

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Until you can identify the specific things that make a person want to be a customer, you don’t have an accurate predictive persona. And that means your product and design decisions will be based on a lie.