"The brokerage industry has lulled us all to sleep and/or taught us that the fees are inconsequential," said Robbins. "Nothing could be further from the truth."
As awareness about fees has grown—due in part to vocal critics like Robbins and Vanguard Group founder Jack Bogle (who, admittedly, stands to benefit from it as his firm pioneered low-cost index funds)—so has the number of lower-cost financial products and services.
Since Bogle launched the first retail index fund in 1976, hundreds of different low-cost index funds have sprung up. The funds, which carry a lower expense ratio than active mutual funds because they trade less often and aren't actively managed, have soared in popularity in recent years. In December,Morningstar reported that over the previous year, active U.S. equity funds lost $91.9 billion in outflows while passive U.S. equity funds drew in $156.1 billion.
That's in large part because there hasn't been a clear correlation between higher fees and better performance, which makes it hard to justify paying more for a fund. Actively managed funds typically have the highest fees, but not always the best performance—something that's been pointed out by critics and researchers in recent years.
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To be fair, some active fund managers do consistently beat the market and earn the extra fees they charge investors. Other managers argue that their true value is in protecting clients from big losses when the market tanks, and not necessarily in delivering the biggest total returns.
But a 2014 report by the S&P Dow Jones Indices found that 60 percent of large-cap managers, 58 percent of mid-cap managers and 73 percent of small-cap managers had underperformed their benchmarks in the previous 12 months. And over the previous five years, more than 70 percent of domestic equity managers had failed to deliver returns higher than their respective benchmarks.
And in an analysis of a million portfolios over the previous 12 months, online investment manager SigFig found that, in general, lower-priced funds consistently performed better than those that cost more.