Those coffee 'cup' machines automate a majority of the series steps and outputs a decent coffee... perfect for office environments or mornings before work where people don't have time to grind or babysit a drip machine.
The value is quite clear in the context of alternatives. Which is where I believe Juicero stumbles when one considers the various alternatives. Especially with the high cost and fast expiration dates.
Additionally, the taste benefit of nespresso over instant coffee or something similar is probably much higher than juicero over the best bottled juice.