She's working her ass off to build a company with a mission far more important than email marketing or advertising or Candy Crush or blockchains.
Were they overly optimistic in their projections? Probably, but try starting a company and not being optimistic. You'll never get off the ground.
Did they not take reasonable precautions in an industry (biotech/healthcare) with serious repercussions? Absolutely. There are very real questions about her empathy and ethics.
That said, let's stop getting giddy every time Theranos (or some other startup) shows weakness. As founders — those "playing startup" excluded — it is incredibly hard. Let's have some empathy ourselves for those who have (likely) fucked up.