What is behind the concept of robo-advice [en]

What is behind the concept of robo-advice, that make prominent players like Schwab to enter into this business as recently reported:
Schwab to offer free ‚robo-advice‘ By Jed Horowitz

As usual robo-advisor services like Betterment or this new service of Schwab do create more or less ‚intelligent portfolios‘ or asset allocations based on ETFs.

The beauty of the concept of an asset allocation based on ETFs is certainly the low fee level. If one puts the initial automated allocation advice for free on top then you can certainly attract fee sensitiv clients.

ETF and such robo-advice services are what other industries would call ‚good enough technology‘ a simplified but cheaper product which is nevertheless (hopefully) robust. It is the Tata car or Dacia SUV of the asset management industry. It is not a Porsche but usually geta you from A to location B.