I can't speak for Wealthfront, but managed "funds" are typically balanced across high and low risk securities. Thus they will obviously lag behind even index funds like SPY/QQQ. Where managed funds tend to show benefits is in times of high volatility or downturns. Ask yourself how many downturns you've seen in the age of Wealthfront. Because I count 0. And 10-15% yearly returns aren't exactly impressive in the last 12 years. SPY stomped those numbers: https://finance.yahoo.com/quote/SPY/performance/