Madoff had an incredibly successful and well run OTC trading platform that was a backbone for NASDAQ. His fraud was done outside of the primary business lines - so it wasn't just straight up selling just himself, he had an auditable track record.
Folks like Madoff are successful because they take advantage of fear and greed.
An "auditable track record" helps but is not required. See http://www.vanityfair.com/news/2008/10/follieri200810 for an example.
Holmes is all they have: a PR-friendly cargo-cult attempted zuckalike
She has no record.
Again, investors in the U.S. are defrauded to the tune of tens of billions of dollars every year. Do you honestly believe that all the perps have stellar track records?
As it relates to Holmes and Theranos, it should first be noted that nobody really knows what's happening, so I don't think anybody can legitimately claim that Theranos is a scam at this point. But to say that Holmes has "no record" is silly. One might have good reason to question how meaningful her accomplishments are and her qualifications to run a business like Theranos, but she comes from a politically-connected family, attended an elite prep school and was a President's Scholar at Stanford. Before she ever reached the age of 20 she had access to, and could command the attention of, powerful and influential people most of us will realistically never be able to call on.