Sign up for Discord without giving my real number?

In Discord’s documentation, on the section about phone number verification, it states “VOIP, Burner, or Landline numbers cannot be used.”

I get how VOIP number ranges are easy to identify and blacklist, but how would Discord know if I’m using a burner number? What kind of burner number are they talking about / what would make it be detected as one? AFAIK Discord doesn’t ask for your real name on signup, so they can’t be trying to match a given …

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