[phillco]

Agree with the sibling comment -- you can achieve a good portfolio allocation with 3-4 ETFs. What Wealthfront and Betterment do is pick these funds for you, then charge you 0.25% year over year for the privilege of maintaining them. It's not the best deal for the investor because the work is not particularly hard -- "managing" your investments as a Boglehead would ideally involve logging into Vanguard once a year to rebalance.

(In fairness, they do some other stuff which is more value-added like TLH, which is more work to do yourself, but again, it's hard to justify the 0.25%.)

"If You Can" by William Berstein is a good, short ebook on this subject.